diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 483ad9f..f12ab33 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -13,7 +13,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: "3.9"
+          python-version: "3.11"
       - name: Cache pip
         uses: actions/cache@v2
         with:
@@ -31,7 +31,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-       python-versions: ["3.7", "3.8", "3.9", "3.10"]
+       python-versions: ["3.8", "3.9", "3.10", "3.11", "3.12"]
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python ${{ matrix.python-versions }}
diff --git a/4.0-Upgrade.md b/4.0-Upgrade.md
new file mode 100644
index 0000000..7173f19
--- /dev/null
+++ b/4.0-Upgrade.md
@@ -0,0 +1,30 @@
+# Upgrading to chartmogul-python 4.0.0
+
+This new version replaces the existing pagination for the `.all()` endpoints that used a combination of `page` and `per_page` parameters, and instead uses a `cursor` based pagination. So to list (as an example) Plans you now can:
+
+```python
+config = Config("your-token")
+
+# Getting the first page
+plans = Plan.all(config, per_page=12)
+
+"""
+This will return an array of plans (if available), and a cursor + has_more fields
+"""
+{
+    "plans": [
+        {
+            "uuid": "some_uuid",
+            "data_source_uuid": "some_uuid",
+            "name": "Master Plan"
+        }
+    ],
+    "has_more": True,
+    "cursor": "MjAyMy0wNy0yOFQwODowOToyMi4xNTQyMDMwMDBaJjk0NDQ0Mg=="
+}
+
+if plans.has_more:
+    more_plans = Plan.all(config, per_page=12, cursor=plans.cursor)
+```
+
+If you have existing code that relies on the `page` parameter, those requests will throw an error now alerting you of their deprecation.
diff --git a/CHANGELOG.md b/CHANGELOG.md
index c91637d..c2071b0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,17 @@ and this project adheres to [Semantic Versioning].
 [Keep a Changelog]: https://keepachangelog.com/en/1.0.0/
 [Semantic Versioning]: https://semver.org/spec/v2.0.0.html
 
+## [4.0.0] - 2023-10-04
+
+### Added
+- v4.0.0 upgrade instructions.
+- Support for Python 3.12.
+
+### Removed
+- Support for old pagination using `page` query params.
+- Deprecated `imp` module.
+- Support for Python 3.7.
+
 ## [3.1.3] - 2023-09-27
 
 ### Added
diff --git a/README.md b/README.md
index f197fff..acaf1cc 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@
 
 ## Installation
 
-This library requires Python 3.5 to 3.9. It was last tested against Python 2.7 in version 1.3.0.
+This library requires Python 3.8 to 3.12. It was last tested against Python 2.7 in version 1.3.0.
 
 ```sh
 pip3 install chartmogul
@@ -376,6 +376,8 @@ To work on the library:
 
 * Fork it
 * Create your feature branch (`git checkout -b my-new-feature`)
+* Setup a virtual environment (`python -m venv <directory>`)
+* Activate the virtual environment (`source <directory>/bin/activate`)
 * Install dependencies: `pip3 install -r requirements.txt && python3 setup.py develop`
 * Fix bugs or add features. Make sure the changes pass the coding guidelines (use `pylama`).
 * Write tests for your new features. Use `requests_mock` for HTTP mocking.
diff --git a/chartmogul/__init__.py b/chartmogul/__init__.py
index 186921a..7c8ff4b 100644
--- a/chartmogul/__init__.py
+++ b/chartmogul/__init__.py
@@ -1,6 +1,11 @@
 # -*- coding: utf-8 -*-
 from .api.config import Config
-from .errors import APIError, ConfigurationError, ArgumentMissingError
+from .errors import (
+    APIError,
+    ConfigurationError,
+    ArgumentMissingError,
+    DeprecatedArgumentError,
+)
 
 from .api.customers.activity import CustomerActivity
 from .api.attributes import Attributes
@@ -24,9 +29,6 @@
 
 from .version import __version__
 
-# Deprecated
-import imp
-
 
 """
 ChartMogul API Python Client
diff --git a/chartmogul/api/customer.py b/chartmogul/api/customer.py
index 8165b37..3bb7199 100644
--- a/chartmogul/api/customer.py
+++ b/chartmogul/api/customer.py
@@ -31,11 +31,7 @@ class Customer(Resource):
 
     _path = "/customers{/uuid}"
     _root_key = "entries"
-    _many = namedtuple(
-        "Customers",
-        [_root_key, "has_more", "per_page", "page", "current_page", "total_pages", "cursor"],
-        defaults=[None, None, None, None, None, None],
-    )
+    _many = namedtuple("Customers", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         # All operations
diff --git a/chartmogul/api/customers/activity.py b/chartmogul/api/customers/activity.py
index de43eb5..660be4e 100644
--- a/chartmogul/api/customers/activity.py
+++ b/chartmogul/api/customers/activity.py
@@ -10,11 +10,7 @@ class CustomerActivity(Resource):
 
     _path = "/customers{/uuid}/activities"
     _root_key = "entries"
-    _many = namedtuple(
-        "Activities",
-        [_root_key, "has_more", "per_page", "page", "cursor"],
-        defaults=[None, None, None, None],
-    )
+    _many = namedtuple("Activities", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         id = fields.Int()
diff --git a/chartmogul/api/customers/subscription.py b/chartmogul/api/customers/subscription.py
index 2d14b9a..1c7dd25 100644
--- a/chartmogul/api/customers/subscription.py
+++ b/chartmogul/api/customers/subscription.py
@@ -11,11 +11,7 @@ class CustomerSubscription(Resource):
 
     _path = "/customers{/uuid}/subscriptions"
     _root_key = "entries"
-    _many = namedtuple(
-        "Subscriptions",
-        [_root_key, "has_more", "per_page", "page", "cursor"],
-        defaults=[None, None, None, None],
-    )
+    _many = namedtuple("Subscriptions", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         id = fields.Int(allow_none=True)
@@ -52,19 +48,10 @@ def _loadJSON(cls, jsonObj):
         if "subscriptions" in jsonObj:
             _many = namedtuple(
                 "Subscriptions",
-                [
-                    "subscriptions",
-                    "current_page",
-                    "total_pages",
-                    "customer_uuid",
-                    "has_more",
-                    "cursor",
-                ],
+                ["subscriptions", "has_more", "cursor", "customer_uuid"],
             )
             return _many(
                 cls._schema.load(jsonObj["subscriptions"], many=True),
-                current_page=jsonObj.get("current_page", None),
-                total_pages=jsonObj.get("total_pages", None),
                 customer_uuid=jsonObj.get("customer_uuid", None),
                 has_more=jsonObj.get("has_more", None),
                 cursor=jsonObj.get("cursor", None),
diff --git a/chartmogul/api/invoice.py b/chartmogul/api/invoice.py
index 43e3abe..967cec9 100644
--- a/chartmogul/api/invoice.py
+++ b/chartmogul/api/invoice.py
@@ -42,8 +42,8 @@ class Invoice(Resource):
     _root_key = "invoices"
     _many = namedtuple(
         "Invoices",
-        [_root_key, "current_page", "total_pages", "cursor", "has_more", "customer_uuid"],
-        defaults=[None, None, None, None, None],
+        [_root_key, "cursor", "has_more", "customer_uuid"],
+        defaults=[None, None, None],
     )
     _many.__new__.__defaults__ = (None,) * len(_many._fields)
 
@@ -82,6 +82,8 @@ def all(cls, config, **kwargs):
 Invoice.all_any = Invoice._method("all", "get", "/invoices")
 Invoice.destroy = Invoice._method("destroy", "delete", "/invoices{/uuid}")
 Invoice.destroy_all = Invoice._method(
-    "destroy_all", "delete", "/data_sources{/data_source_uuid}/customers{/customer_uuid}/invoices"
+    "destroy_all",
+    "delete",
+    "/data_sources{/data_source_uuid}/customers{/customer_uuid}/invoices",
 )
 Invoice.retrieve = Invoice._method("retrieve", "get", "/invoices{/uuid}")
diff --git a/chartmogul/api/plan.py b/chartmogul/api/plan.py
index d35b373..43899d2 100644
--- a/chartmogul/api/plan.py
+++ b/chartmogul/api/plan.py
@@ -10,11 +10,7 @@ class Plan(Resource):
 
     _path = "/plans{/uuid}"
     _root_key = "plans"
-    _many = namedtuple(
-        "Plans",
-        [_root_key, "current_page", "total_pages", "has_more", "cursor"],
-        defaults=[None, None, None, None],
-    )
+    _many = namedtuple("Plans", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         uuid = fields.String()
diff --git a/chartmogul/api/plan_group.py b/chartmogul/api/plan_group.py
index 105601b..bf72dee 100644
--- a/chartmogul/api/plan_group.py
+++ b/chartmogul/api/plan_group.py
@@ -11,11 +11,7 @@ class PlanGroup(Resource):
 
     _path = "/plan_groups{/uuid}"
     _root_key = "plan_groups"
-    _many = namedtuple(
-        "PlanGroups",
-        [_root_key, "current_page", "total_pages", "has_more", "cursor"],
-        defaults=[None, None, None, None],
-    )
+    _many = namedtuple("PlanGroups", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         uuid = fields.String()
diff --git a/chartmogul/api/plan_group_plans.py b/chartmogul/api/plan_group_plans.py
index 4b01832..393cb68 100644
--- a/chartmogul/api/plan_group_plans.py
+++ b/chartmogul/api/plan_group_plans.py
@@ -10,11 +10,7 @@ class PlanGroupPlans(Resource):
 
     _path = "/plan_groups{/uuid}/plans"
     _root_key = "plans"
-    _many = namedtuple(
-        "PlanGroupPlans",
-        [_root_key, "current_page", "total_pages", "has_more", "cursor"],
-        defaults=[None, None, None, None],
-    )
+    _many = namedtuple("PlanGroupPlans", [_root_key, "has_more", "cursor"], defaults=[None, None])
 
     class _Schema(Schema):
         uuid = fields.String()
diff --git a/chartmogul/api/subscription_event.py b/chartmogul/api/subscription_event.py
index 6d65c05..03fe908 100644
--- a/chartmogul/api/subscription_event.py
+++ b/chartmogul/api/subscription_event.py
@@ -11,7 +11,7 @@ class SubscriptionEvent(Resource):
     _path = "/subscription_events"
     _root_key = "subscription_events"
     _many = namedtuple(
-        "SubscriptionEvents", [_root_key, "meta", "has_more", "cursor"], defaults=[None, None, None]
+        "SubscriptionEvents", [_root_key, "has_more", "cursor"], defaults=[None, None]
     )
 
     class _Schema(Schema):
diff --git a/chartmogul/errors.py b/chartmogul/errors.py
index 50d1ebc..924a82c 100644
--- a/chartmogul/errors.py
+++ b/chartmogul/errors.py
@@ -14,6 +14,10 @@ class ArgumentMissingError(Exception):
     pass
 
 
+class DeprecatedArgumentError(Exception):
+    pass
+
+
 def annotateHTTPError(err):
     if isinstance(err, HTTPError):
         raise_from(APIError(err.response.content), err)
diff --git a/chartmogul/imp/__init__.py b/chartmogul/imp/__init__.py
deleted file mode 100644
index a02d826..0000000
--- a/chartmogul/imp/__init__.py
+++ /dev/null
@@ -1,4 +0,0 @@
-# Deprecated
-from .invoice import Invoice
-from .transaction import Transaction
-from .subscription import Subscription
diff --git a/chartmogul/imp/invoice.py b/chartmogul/imp/invoice.py
deleted file mode 100644
index 8078d6f..0000000
--- a/chartmogul/imp/invoice.py
+++ /dev/null
@@ -1,14 +0,0 @@
-from ..api.invoice import Invoice as InvoiceNew
-from warnings import warn
-
-
-class Invoice(InvoiceNew):
-    @classmethod
-    def create(cls, *args, **kwargs):
-        warn("chartmogul.imp namespace is deprecated, use chartmogul.Invoice.create!")
-        return super(Invoice, cls).create(*args, **kwargs)
-
-    @classmethod
-    def all(cls, *args, **kwargs):
-        warn("chartmogul.imp namespace is deprecated, use chartmogul.Invoice.all!")
-        return super(Invoice, cls).all(*args, **kwargs)
diff --git a/chartmogul/imp/subscription.py b/chartmogul/imp/subscription.py
deleted file mode 100644
index 24051c1..0000000
--- a/chartmogul/imp/subscription.py
+++ /dev/null
@@ -1,16 +0,0 @@
-from ..api.customers.subscription import CustomerSubscription as SubsNew
-from warnings import warn
-
-
-class Subscription(SubsNew):
-    @classmethod
-    def all(cls, *args, **kwargs):
-        warn(
-            "chartmogul.imp namespace is deprecated, use chartmogul.CustomerSubscription.list_imported!"
-        )
-        return super(Subscription, cls).list_imported(*args, **kwargs)
-
-    @classmethod
-    def cancel(cls, *args, **kwargs):
-        warn("chartmogul.imp namespace is deprecated, use chartmogul.CustomerSubscription.cancel!")
-        return super(Subscription, cls).cancel(*args, **kwargs)
diff --git a/chartmogul/imp/transaction.py b/chartmogul/imp/transaction.py
deleted file mode 100644
index c189d4f..0000000
--- a/chartmogul/imp/transaction.py
+++ /dev/null
@@ -1,9 +0,0 @@
-from ..api.transaction import Transaction as TransactionNew
-from warnings import warn
-
-
-class Transaction(TransactionNew):
-    @classmethod
-    def create(cls, *args, **kwargs):
-        warn("chartmogul.imp namespace is deprecated, use chartmogul.Transaction.create!")
-        return super(Transaction, cls).create(*args, **kwargs)
diff --git a/chartmogul/resource.py b/chartmogul/resource.py
index 6521bf3..bdfffab 100644
--- a/chartmogul/resource.py
+++ b/chartmogul/resource.py
@@ -5,7 +5,12 @@
 from uritemplate import URITemplate
 
 from .api.config import Config
-from .errors import ArgumentMissingError, ConfigurationError, annotateHTTPError
+from .errors import (
+    ArgumentMissingError,
+    ConfigurationError,
+    annotateHTTPError,
+    DeprecatedArgumentError,
+)
 from .retry_request import requests_retry_session
 
 from .version import __version__
@@ -29,18 +34,7 @@
     "modify_with_params": "patch",
 }
 
-LIST_PARAMS = [
-    "current_page",
-    "total_pages",
-    "has_more",
-    "per_page",
-    "page",
-    "summary",
-    "customer_uuid",
-    "data_source_uuid",
-    "cursor",
-    "meta",
-]
+LIST_PARAMS = ["has_more", "summary", "customer_uuid", "data_source_uuid", "cursor"]
 ESCAPED_QUERY_KEYS = {"start_date": "start-date", "end_date": "end-date"}
 
 
@@ -175,6 +169,8 @@ def _validate_arguments(cls, method, kwargs):
             raise ArgumentMissingError("Please pass 'uuid' parameter")
         if method in ["create", "modify"] and "data" not in kwargs:
             raise ArgumentMissingError("Please pass 'data' parameter")
+        if method == "all" and "page" in kwargs:
+            raise DeprecatedArgumentError("The 'page' parameter is deprecated")
         if (
             method in ["destroy_all"]
             and "data_source_uuid" not in kwargs
diff --git a/chartmogul/version.py b/chartmogul/version.py
index f749372..ce1305b 100644
--- a/chartmogul/version.py
+++ b/chartmogul/version.py
@@ -1 +1 @@
-__version__ = "3.1.3"
+__version__ = "4.0.0"
diff --git a/docs/chartmogul.imp.rst b/docs/chartmogul.imp.rst
deleted file mode 100644
index e59f11d..0000000
--- a/docs/chartmogul.imp.rst
+++ /dev/null
@@ -1,10 +0,0 @@
-chartmogul.imp package
-======================
-
-Module contents
----------------
-
-.. automodule:: chartmogul.imp
-    :members:
-    :undoc-members:
-    :show-inheritance:
diff --git a/docs/chartmogul.rst b/docs/chartmogul.rst
index 1460bf4..f5cedd2 100644
--- a/docs/chartmogul.rst
+++ b/docs/chartmogul.rst
@@ -8,7 +8,6 @@ Subpackages
 
     chartmogul.api
     chartmogul.enrichment
-    chartmogul.imp
     chartmogul.metrics
 
 Submodules
diff --git a/docs/test.imp.rst b/docs/test.imp.rst
deleted file mode 100644
index fe94e8a..0000000
--- a/docs/test.imp.rst
+++ /dev/null
@@ -1,30 +0,0 @@
-test.imp package
-================
-
-Submodules
-----------
-
-test.imp.test_invoice module
-----------------------------
-
-.. automodule:: test.imp.test_invoice
-    :members:
-    :undoc-members:
-    :show-inheritance:
-
-test.imp.test_subscription module
----------------------------------
-
-.. automodule:: test.imp.test_subscription
-    :members:
-    :undoc-members:
-    :show-inheritance:
-
-
-Module contents
----------------
-
-.. automodule:: test.imp
-    :members:
-    :undoc-members:
-    :show-inheritance:
diff --git a/fixtures/fetch_account.yaml b/fixtures/fetch_account.yaml
new file mode 100644
index 0000000..017da13
--- /dev/null
+++ b/fixtures/fetch_account.yaml
@@ -0,0 +1,60 @@
+interactions:
+- request:
+    body: null
+    headers:
+      Accept:
+      - '*/*'
+      Accept-Encoding:
+      - gzip, deflate
+      Connection:
+      - keep-alive
+      User-Agent:
+      - chartmogul-python/4.0.0
+      content-type:
+      - application/json
+    method: GET
+    uri: https://api.chartmogul.com/v1/account
+  response:
+    body:
+      string: '{"name":"Chartmogul Test","currency":"EUR","time_zone":"Europe/Lisbon","week_start_on":"monday"}'
+    headers:
+      Access-Control-Allow-Credentials:
+      - 'true'
+      Access-Control-Allow-Headers:
+      - Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept,Authorization
+      Access-Control-Allow-Methods:
+      - GET, OPTIONS
+      Access-Control-Allow-Origin:
+      - '*'
+      Cache-Control:
+      - max-age=0, private, must-revalidate
+      Connection:
+      - keep-alive
+      Content-Length:
+      - '96'
+      Content-Type:
+      - application/json; charset=utf-8
+      Date:
+      - Sun, 10 Sep 2023 20:18:46 GMT
+      ETag:
+      - W/"4c95c647e6119fa4820a4ca4d344ec3d"
+      Referrer-Policy:
+      - strict-origin-when-cross-origin
+      X-Content-Type-Options:
+      - nosniff
+      X-Download-Options:
+      - noopen
+      X-Frame-Options:
+      - DENY
+      X-Permitted-Cross-Domain-Policies:
+      - none
+      X-Request-Id:
+      - a388e7b97b3cdbb5aceba74e80d345fc
+      X-Runtime:
+      - '0.022753'
+      X-XSS-Protection:
+      - 1; mode=block
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/fixtures/fetch_subscription_events.yaml b/fixtures/fetch_subscription_events.yaml
deleted file mode 100644
index bc1427d..0000000
--- a/fixtures/fetch_subscription_events.yaml
+++ /dev/null
@@ -1,78 +0,0 @@
-interactions:
-- request:
-    body: null
-    headers:
-      Accept:
-      - '*/*'
-      Accept-Encoding:
-      - gzip, deflate
-      Connection:
-      - keep-alive
-      User-Agent:
-      - chartmogul-python/3.1.2
-      content-type:
-      - application/json
-    method: GET
-    uri: https://api.chartmogul.com/v1/subscription_events
-  response:
-    body:
-      string: !!binary |
-        H4sIAAAAAAAAA+2bXZOiOBSG/wvX7VS+P/wdfbVbUxRCUEGQhmDrdPV/3xC2dtepHRkJAbvKKm+U
-        Qzwkj29OXpOPoGk3TVzvK70/lqE6qVI3wfrPj2CfBGtMuUQCE/QSJJGOwubY1rEK27a7GCRNKDFM
-        oYzQKuZJuoJQJauNgnKVbjiPUkaTKJHBSxC3jT4Wqg7VWau6jA6hbYBDCTg0169yaJS+jivbw+Gn
-        mOt2ENn94Ni0Ux0i8wz//Y7+XvtYoXkEZdJGAOEVoCvIXwFbI7BG/A9zr0pTFev9Sf0cB/ArAGv7
-        snFdF4X6UnVtXSUeR2WsDgeVdK39TxJ1faxN3358mg6plUkmCSP964Taqkv4dsxbG5V6ry/Bun/Q
-        uK1rVcb/vI+KY2uy3Zdh3A9sH6ajc/iLS7XSdRR339t3WjdQ3U2fL9dIQD9IQMEA64byqmfvRyLP
-        i0bwJxLdb28uJIAfJBCkEDB3JLIs3V2a8UiwR1MJm9CAStiYxVQCSz9IECoRBRMgQTWrd96QQLNP
-        HF8ACeEHCSgQ7/Tecd7Y/mDYRSTobZGYnwib0IBI2JjlRIL7IYIhTlBXfboiEVfbs0N1+USiW1H0
-        hedvVpeY+UGCI8anmDc4T6pdNX7eII+mEjahAZWwMcupBPWDBKPUCIW7SuzqgorMGxLzr0G/ABLE
-        DxIQE47ciSCIxuVlPBH4tkjMT4RNaEAkbMxyIoH9EMEwR3gCV4LSfBN39tBIo+qJxP2lBPKEBAFi
-        CiSy8j19I+ORQI+mEjahAZWwMcuphCfvEhufindD6bjgIO8sSRxKiScS96uEJ++SAmjcS3ckUiYY
-        EuNVAj6aStiEBlTCxiymEsiTUcUwIXgCJHBxZmeHWmIAifmdqi+AhCdbgmEq4QROVYbzt62DSoDb
-        KjE/EjahAZWwMcuphCdbAgsMYDeUjrVE9l7k0sGpeiJxdy2BPNkS2FhVeILyMs0zWejRtQSUD6YS
-        fUK3VaKPWU4lPPkSxGzOYRMgIZDcvT+RMLuMZtstgZAfX4JALsQEuyVEqk+X8RMHFE+VuPdfL+TJ
-        l6AcCzGFSmRbpLt2xrmXQ0jMbmj3CQ1MHJbj5SYOj76EnOI/jktRoicSc04c0JMvATGXdIIVx1an
-        cZqNV4lH24wLbUIDKmFjFlMJ6GkHDSGSsAmQwLu3bONQSzyRuHsRCj2tOIyhjRkwv25HXyLfpCfq
-        oBKPthkX/sbOyz5mOZXwteKQUoAJ3Euc0wt2WIQOIDG7e/mQSHx/CQqlI3MKJSjNGZUwV+asyN/H
-        fKABpKrVqf+w37C3UemxVv0n/56cka8QralYQ/oNY2sRVtHWnIcxCxh91OZ4T/fWLH8I4p+ffwGd
-        9Me3YzQAAA==
-    headers:
-      Access-Control-Allow-Credentials:
-      - 'true'
-      Cache-Control:
-      - max-age=0, private, must-revalidate
-      Connection:
-      - keep-alive
-      Content-Encoding:
-      - gzip
-      Content-Length:
-      - '1033'
-      Content-Type:
-      - application/json; charset=utf-8
-      Date:
-      - Fri, 19 May 2023 12:58:15 GMT
-      ETag:
-      - W/"81eb5df6ece395240b6951a8223b5f5d"
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-      X-Frame-Options:
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diff --git a/requirements-test.txt b/requirements-test.txt
index 1853eca..502cf79 100644
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,8 +1,7 @@
 -r requirements.txt
-yarl
-mock>=1.0.1
-requests-mock>=1.3.0
-vcrpy<3.0.0
-PyYAML>=5.1.2
-httpretty>=0.9.6
-wrapt>=1.11.2
+mock>=5.1.0
+requests-mock>=1.11.0
+vcrpy>=4.4.0
+PyYAML>=6.0.1
+httpretty>=1.1.4
+wrapt>=1.15.0
diff --git a/requirements.txt b/requirements.txt
index e62d693..ab36637 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,6 @@
 requests>=2.10.0
 uritemplate>=3.0.0
 promise>=1.0.1
-marshmallow>=3.10.0
+marshmallow>=3.19.0
 future>=0.18.3
-urllib3<2.0
-vcrpy<=4.0.0
\ No newline at end of file
+urllib3<=2.0.4
diff --git a/setup.py b/setup.py
index a9164d2..939c1e6 100644
--- a/setup.py
+++ b/setup.py
@@ -14,28 +14,26 @@
     sys.exit()
 
 requires = [
-    "requests>=2.10.0",
-    "uritemplate>=3.0.0",
-    "promise>=1.0.1",
-    "marshmallow>=3.10.0",
+    "requests>=2.31.0",
+    "uritemplate>=4.1.1",
+    "promise>=2.3.0",
+    "marshmallow>=3.19.0",
     "future>=0.18.3",
-    "urllib3<2.0",
+    "urllib3<=2.0.4",
 ]
 test_requirements = [
-    # This is needed to circumvent a vcrpy dependency problem And can be
-    # deleted once it is solved.
-    'yarl; python_version>"3.5"',
-    'yarl<1.4; python_version=="3.5"',
-    "mock>=1.0.1",
-    "requests-mock>=1.3.0",
-    "vcrpy<3.0.0",
-    "PyYAML>=5.1.2",
-    "httpretty>=0.9.6",
-    "wrapt>=1.11.2",
+    "mock>=5.1.0",
+    "requests-mock>=1.11.0",
+    "vcrpy>=4.4.0",
+    "PyYAML>=6.0.1",
+    "httpretty>=1.1.4",
+    "wrapt>=1.15.0",
 ]
 
 with open("chartmogul/version.py", "r") as fd:
-    version = re.search(r'^__version__\s*=\s*[\'"]([^\'"]*)[\'"]', fd.read(), re.MULTILINE).group(1)
+    version = re.search(
+        r'^__version__\s*=\s*[\'"]([^\'"]*)[\'"]', fd.read(), re.MULTILINE
+    ).group(1)
 
 if not version:
     raise RuntimeError("Cannot find version information")
@@ -49,12 +47,15 @@
     author_email="petr@chartmogul.com",
     url="https://chartmogul.com",
     download_url=github_url + "/tarball/v" + version,
-    packages=["chartmogul", "chartmogul.api", "chartmogul.imp", "chartmogul.api.customers"],
+    packages=[
+        "chartmogul",
+        "chartmogul.api",
+        "chartmogul.api.customers",
+    ],
     package_data={"": ["LICENSE", "NOTICE"], "chartmogul": ["*.pem"]},
     package_dir={
         "chartmogul": "chartmogul",
         "chartmogul.api": "chartmogul/api",
-        "chartmogul.imp": "chartmogul/imp",
         "chartmogul.api.customers": "chartmogul/api/customers",
     },
     include_package_data=True,
@@ -67,9 +68,10 @@
     classifiers=[
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
+        "Programming Language :: Python :: 3.12",
     ],
 )
diff --git a/test/api/test_activity.py b/test/api/test_activity.py
index 1b7a631..4e7834c 100644
--- a/test/api/test_activity.py
+++ b/test/api/test_activity.py
@@ -38,7 +38,6 @@ def test_all(self, mock_requests):
                     },
                 ],
                 "has_more": False,
-                "per_page": 200,
                 "cursor": "cursor==",
             },
         )
diff --git a/test/api/test_common.py b/test/api/test_common.py
index 115b248..e8131e6 100644
--- a/test/api/test_common.py
+++ b/test/api/test_common.py
@@ -4,7 +4,13 @@
 import requests_mock
 from requests.exceptions import HTTPError
 
-from chartmogul import DataSource, Config, APIError, ArgumentMissingError
+from chartmogul import (
+    DataSource,
+    Config,
+    APIError,
+    ArgumentMissingError,
+    DeprecatedArgumentError,
+)
 
 
 class CommonTestCase(unittest.TestCase):
@@ -15,7 +21,9 @@ class CommonTestCase(unittest.TestCase):
     @requests_mock.mock()
     def test_forget_uuid_destroy(self, mock_requests):
         mock_requests.register_uri(
-            "DELETE", "https://api.chartmogul.com/v1/data_sources/my_uuid", status_code=204
+            "DELETE",
+            "https://api.chartmogul.com/v1/data_sources/my_uuid",
+            status_code=204,
         )
         mock_requests.register_uri(
             "DELETE",
@@ -58,13 +66,38 @@ def test_forget_uuid_retrieve(self, mock_requests):
         else:
             self.fail("ArgumentMissingError not raised")
 
+    @requests_mock.mock()
+    def test_page_parameter_deprecated(self, mock_requests):
+        mock_requests.register_uri(
+            "GET",
+            "https://api.chartmogul.com/v1/data_sources?page=1",
+            status_code=400,
+            json={
+                "code": 400,
+                "message": 'Parameter "page" is deprecated',
+                "param": "page",
+            },
+        )
+
+        config = Config("token")
+        try:
+            DataSource.all(config, page=1).get()
+        except DeprecatedArgumentError:
+            pass
+        else:
+            self.fail("DeprecatedArgumentError not raised")
+
     @requests_mock.mock()
     def test_api_incorrect(self, mock_requests):
         mock_requests.register_uri(
             "POST",
             "https://api.chartmogul.com/v1/data_sources",
             status_code=400,
-            json={"code": 400, "message": 'Parameter "name" is missing', "param": "name"},
+            json={
+                "code": 400,
+                "message": 'Parameter "name" is missing',
+                "param": "name",
+            },
         )
 
         config = Config("token")
diff --git a/test/api/test_customer.py b/test/api/test_customer.py
index 9d5f4bf..d82fc73 100644
--- a/test/api/test_customer.py
+++ b/test/api/test_customer.py
@@ -76,15 +76,7 @@
     "currency-sign": "$",
 }
 
-allContactsOld = {
-    "entries": [entry],
-    "per_page": 50,
-    "page": 1,
-    "current_page": 1,
-    "total_pages": 4,
-}
-
-allContactsNew = {"entries": [entry], "cursor": "cursor==", "has_more": True}
+allContacts = {"entries": [entry], "cursor": "cursor==", "has_more": True}
 
 deserializedCustomer = Customer(
     id=25647,
@@ -294,49 +286,13 @@ class CustomerTestCase(unittest.TestCase):
     """
 
     @requests_mock.mock()
-    def test_all_old_pagination(self, mock_requests):
-        mock_requests.register_uri(
-            "GET",
-            "https://api.chartmogul.com/v1/customers",
-            request_headers={"Authorization": "Basic dG9rZW46"},
-            status_code=200,
-            json=allContactsOld,
-        )
-
-        config = Config("token")
-        customers = Customer.all(config).get()
-
-        expected = Customer._many(
-            entries=[deserializedCustomer], per_page=50, page=1, current_page=1, total_pages=4
-        )
-
-        self.assertEqual(mock_requests.call_count, 1, "expected call")
-        self.assertEqual(mock_requests.last_request.qs, {})
-        self.assertEqual(mock_requests.last_request.text, None)
-        # Complete comparing too complicated, would need to:
-        #  1) sort all dictionaries,
-        #  2) use special class/library for timezones (Python has no default)
-        # self.assertEqual(str(customers), str(expected))
-        # => check only first level fields are OK
-        self.assertEqual(sorted(dir(customers)), sorted(dir(expected)))
-        self.assertEqual(
-            sorted(customers.entries[0].attributes.stripe),
-            sorted(expected.entries[0].attributes.stripe),
-        )
-        self.assertEqual(
-            sorted(customers.entries[0].attributes.clearbit),
-            sorted(expected.entries[0].attributes.clearbit),
-        )
-        self.assertTrue(isinstance(customers.entries[0], Customer))
-
-    @requests_mock.mock()
-    def test_all_new_pagination(self, mock_requests):
+    def test_all(self, mock_requests):
         mock_requests.register_uri(
             "GET",
             "https://api.chartmogul.com/v1/customers",
             request_headers={"Authorization": "Basic dG9rZW46"},
             status_code=200,
-            json=allContactsNew,
+            json=allContacts,
         )
 
         config = Config("token")
@@ -366,7 +322,10 @@ def test_all_new_pagination(self, mock_requests):
     @requests_mock.mock()
     def test_create(self, mock_requests):
         mock_requests.register_uri(
-            "POST", "https://api.chartmogul.com/v1/customers", status_code=200, json=entry
+            "POST",
+            "https://api.chartmogul.com/v1/customers",
+            status_code=200,
+            json=entry,
         )
 
         config = Config("token")
@@ -376,31 +335,12 @@ def test_create(self, mock_requests):
         self.assertEqual(mock_requests.last_request.json(), sentCreateExpected)
 
     @requests_mock.mock()
-    def test_search_old_pagination(self, mock_requests):
-        mock_requests.register_uri(
-            "GET",
-            "https://api.chartmogul.com/v1/customers/search?email=tralala@someemail.com",
-            status_code=200,
-            json=allContactsOld,
-        )
-
-        config = Config("token")
-        result = Customer.search(config, email="tralala@someemail.com").get()
-        self.assertEqual(mock_requests.call_count, 1, "expected call")
-        self.assertEqual(mock_requests.last_request.qs, {"email": ["tralala@someemail.com"]})
-        self.assertEqual(mock_requests.last_request.text, None)
-        self.assertTrue(isinstance(result, Customer._many))
-        self.assertTrue(isinstance(result.entries[0], Customer))
-        self.assertEqual(result.current_page, 1)
-        self.assertEqual(result.total_pages, 4)
-
-    @requests_mock.mock()
-    def test_search_new_pagination(self, mock_requests):
+    def test_search(self, mock_requests):
         mock_requests.register_uri(
             "GET",
             "https://api.chartmogul.com/v1/customers/search?email=tralala@someemail.com",
             status_code=200,
-            json=allContactsNew,
+            json=allContacts,
         )
 
         config = Config("token")
@@ -507,12 +447,12 @@ def test_contacts(self, mock_requests):
             "GET",
             "https://api.chartmogul.com/v1/customers/cus_00000000-0000-0000-0000-000000000000/contacts",
             status_code=200,
-            json=allContactsNew,
+            json=allContacts,
         )
 
         config = Config("token")
         contacts = Customer.contacts(config, uuid="cus_00000000-0000-0000-0000-000000000000").get()
-        expected = Contact._many(**allContactsNew)
+        expected = Contact._many(**allContacts)
 
         self.assertEqual(mock_requests.call_count, 1, "expected call")
         self.assertEqual(mock_requests.last_request.qs, {})
diff --git a/test/api/test_customers/test_activity.py b/test/api/test_customers/test_activity.py
index 3dac82c..2fe645e 100644
--- a/test/api/test_customers/test_activity.py
+++ b/test/api/test_customers/test_activity.py
@@ -35,7 +35,6 @@ def test_all(self, mock_requests):
                 ],
                 "has_more": False,
                 "per_page": 200,
-                "page": 1,
                 "cursor": "cursor==",
             },
         )
diff --git a/test/api/test_customers/test_subscription.py b/test/api/test_customers/test_subscription.py
index 563a3d4..4f94d0c 100644
--- a/test/api/test_customers/test_subscription.py
+++ b/test/api/test_customers/test_subscription.py
@@ -30,7 +30,9 @@ def test_cancel_subscription(self, mock_requests):
         )
         config = Config("token")  # is actually checked in mock
         result = CustomerSubscription.cancel(
-            config, uuid="some_uuid", data={"cancelled_at": datetime(2016, 1, 15, 0, 0, 0)}
+            config,
+            uuid="some_uuid",
+            data={"cancelled_at": datetime(2016, 1, 15, 0, 0, 0)},
         ).get()
 
         self.assertEqual(mock_requests.call_count, 1, "expected call")
@@ -110,6 +112,8 @@ def test_list_imported_subscriptions(self, mock_requests):
         self.assertEqual(mock_requests.last_request.qs, {})
         self.assertEqual(result.__class__.__name__, CustomerSubscription._many.__name__)
         self.assertEqual(result.customer_uuid, "some_uuid")
+        self.assertEqual(result.cursor, "cursor==")
+        self.assertFalse(result.has_more)
 
     @requests_mock.mock()
     def test_all(self, mock_requests):
@@ -139,7 +143,6 @@ def test_all(self, mock_requests):
                 ],
                 "has_more": False,
                 "per_page": 200,
-                "page": 1,
                 "cursor": "cursor==",
             },
         )
@@ -150,5 +153,5 @@ def test_all(self, mock_requests):
         self.assertEqual(mock_requests.last_request.qs, {})
         self.assertEqual(result.__class__.__name__, CustomerSubscription._many.__name__)
         self.assertEqual(result.entries[0].external_id, "sub_0001")
-        self.assertEqual(result.page, 1)
         self.assertEqual(result.cursor, "cursor==")
+        self.assertFalse(result.has_more)
diff --git a/test/api/test_invoice.py b/test/api/test_invoice.py
index 24cabb4..0f362e7 100644
--- a/test/api/test_invoice.py
+++ b/test/api/test_invoice.py
@@ -166,66 +166,7 @@
     ]
 }
 
-oldInvoiceListExample = {
-    "invoices": [
-        {
-            "uuid": "inv_565c73b2-85b9-49c9-a25e-2b7df6a677c9",
-            "customer_uuid": "cus_f466e33d-ff2b-4a11-8f85-417eb02157a7",
-            "external_id": "INV0001",
-            "date": "2015-11-01T00:00:00.000Z",
-            "due_date": "2015-11-15T00:00:00.000Z",
-            "currency": "USD",
-            "line_items": [
-                {
-                    "uuid": "li_d72e6843-5793-41d0-bfdf-0269514c9c56",
-                    "external_id": None,
-                    "type": "subscription",
-                    "subscription_uuid": "sub_e6bc5407-e258-4de0-bb43-61faaf062035",
-                    "plan_uuid": "pl_eed05d54-75b4-431b-adb2-eb6b9e543206",
-                    "prorated": False,
-                    "service_period_start": "2015-11-01T00:00:00.000Z",
-                    "service_period_end": "2015-12-01T00:00:00.000Z",
-                    "amount_in_cents": 5000,
-                    "quantity": 1,
-                    "discount_code": "PSO86",
-                    "discount_amount_in_cents": 1000,
-                    "tax_amount_in_cents": 900,
-                    "account_code": None,
-                },
-                {
-                    "uuid": "li_0cc8c112-beac-416d-af11-f35744ca4e83",
-                    "external_id": None,
-                    "type": "one_time",
-                    "description": "Setup Fees",
-                    "amount_in_cents": 2500,
-                    "quantity": 1,
-                    "discount_code": "PSO86",
-                    "discount_amount_in_cents": 500,
-                    "tax_amount_in_cents": 450,
-                    "account_code": None,
-                    "discount_description": "Special 20 % discount",
-                    "transaction_fees_in_cents": 50,
-                    "transaction_fees_currency": "CZK",
-                    "event_order": 5,
-                },
-            ],
-            "transactions": [
-                {
-                    "uuid": "tr_879d560a-1bec-41bb-986e-665e38a2f7bc",
-                    "external_id": None,
-                    "type": "payment",
-                    "date": "2015-11-05T00:14:23.000Z",
-                    "result": "successful",
-                }
-            ],
-        }
-    ],
-    "current_page": 1,
-    "total_pages": 1,
-}
-
-
-newInvoiceListExample = {
+invoiceListExample = {
     "invoices": [
         {
             "uuid": "inv_565c73b2-85b9-49c9-a25e-2b7df6a677c9",
@@ -366,8 +307,8 @@ def test_create(self, mock_requests):
     @requests_mock.mock()
     def test_list_has_customer_uuid(self, mock_requests):
         responseData["customer_uuid"] = "UUID"
-        responseData["total_pages"] = 1
-        responseData["current_page"] = 1
+        responseData["cursor"] = None
+        responseData["has_more"] = False
 
         mock_requests.register_uri(
             "GET",
@@ -388,8 +329,8 @@ def test_list_has_customer_uuid(self, mock_requests):
         self.assertTrue(isinstance(result.invoices[0], Invoice))
         self.assertEqual(result.invoices[0].uuid, "inv_565c73b2-85b9-49c9-a25e-2b7df6a677c9")
         self.assertEqual(result.customer_uuid, "UUID")
-        self.assertEqual(result.total_pages, 1)
-        self.assertEqual(result.current_page, 1)
+        self.assertEqual(result.cursor, None)
+        self.assertFalse(result.has_more)
 
     @requests_mock.mock()
     def test_new_list_old_pagination(self, mock_requests):
@@ -402,47 +343,14 @@ def test_new_list_old_pagination(self, mock_requests):
             request_headers={"Authorization": "Basic dG9rZW46"},
             headers={"Content-Type": "application/json"},
             status_code=200,
-            json=oldInvoiceListExample,
+            json=invoiceListExample,
         )
 
         config = Config("token")  # is actually checked in mock
         result = Invoice.all(
-            config, customer_uuid="cus_f466e33d-ff2b-4a11-8f85-417eb02157a7", external_id="INV0001"
-        ).get()
-
-        self.assertEqual(mock_requests.call_count, 1, "expected call")
-        cu = []
-        cu.append("cus_f466e33d-ff2b-4a11-8f85-417eb02157a7")
-        ei = []
-        ei.append("inv0001")
-        self.assertEqual(mock_requests.last_request.qs, {"customer_uuid": cu, "external_id": ei})
-        # Struct too complex to do 1:1 comparison
-        self.assertTrue(isinstance(result, Invoice._many))
-        self.assertEqual(len(result.invoices), 1)
-
-        self.assertEqual(
-            result.invoices[0].customer_uuid, "cus_f466e33d-ff2b-4a11-8f85-417eb02157a7"
-        )
-        self.assertEqual(result.current_page, 1)
-        self.assertEqual(result.total_pages, 1)
-
-    @requests_mock.mock()
-    def test_new_list_new_pagination(self, mock_requests):
-        mock_requests.register_uri(
-            "GET",
-            (
-                "https://api.chartmogul.com/v1/invoices"
-                "?external_id=INV0001&customer_uuid=cus_f466e33d-ff2b-4a11-8f85-417eb02157a7"
-            ),
-            request_headers={"Authorization": "Basic dG9rZW46"},
-            headers={"Content-Type": "application/json"},
-            status_code=200,
-            json=newInvoiceListExample,
-        )
-
-        config = Config("token")  # is actually checked in mock
-        result = Invoice.all(
-            config, customer_uuid="cus_f466e33d-ff2b-4a11-8f85-417eb02157a7", external_id="INV0001"
+            config,
+            customer_uuid="cus_f466e33d-ff2b-4a11-8f85-417eb02157a7",
+            external_id="INV0001",
         ).get()
 
         self.assertEqual(mock_requests.call_count, 1, "expected call")
@@ -458,8 +366,8 @@ def test_new_list_new_pagination(self, mock_requests):
         self.assertEqual(
             result.invoices[0].customer_uuid, "cus_f466e33d-ff2b-4a11-8f85-417eb02157a7"
         )
-        self.assertFalse(result.has_more)
         self.assertEqual(result.cursor, "cursor==")
+        self.assertFalse(result.has_more)
 
     @requests_mock.mock()
     def test_delete(self, mock_requests):
diff --git a/test/api/test_plan.py b/test/api/test_plan.py
index c0f4776..b95e4a1 100644
--- a/test/api/test_plan.py
+++ b/test/api/test_plan.py
@@ -10,10 +10,8 @@ class PlanTestCase(unittest.TestCase):
     Tests cursor query parameters & modify (patch a plan).
     """
 
-    maxDiff = None
-
     @requests_mock.mock()
-    def test_cursor_list_plans_old_pagination(self, mock_requests):
+    def test_cursor_list_plans(self, mock_requests):
         expected_plan_dict = {
             "uuid": "whatever_uuid",
             "data_source_uuid": "some_uuid",
@@ -25,62 +23,37 @@ def test_cursor_list_plans_old_pagination(self, mock_requests):
         mock_requests.register_uri(
             "GET",
             (
-                "https://api.chartmogul.com/v1/plans?page=5"
+                "https://api.chartmogul.com/v1/plans?"
                 "&per_page=12&data_source_uuid=some_uuid&external_id=custom_filter"
             ),
             request_headers={"Authorization": "Basic dG9rZW46"},
             status_code=200,
-            json={"plans": [expected_plan_dict], "current_page": 5, "total_pages": 18},
+            json={
+                "plans": [expected_plan_dict],
+                "cursor": "cursor==",
+                "has_more": False,
+            },
         )
         config = Config("token")  # is actually checked in mock
         plan = Plan.all(
-            config, page=5, per_page=12, data_source_uuid="some_uuid", external_id="custom_filter"
+            config,
+            per_page=12,
+            data_source_uuid="some_uuid",
+            external_id="custom_filter",
         ).get()
-        expected = Plan._many([Plan(**expected_plan_dict)], current_page=5, total_pages=18)
+        expected = Plan._many([Plan(**expected_plan_dict)], cursor="cursor==", has_more=False)
         self.assertEqual(mock_requests.call_count, 1, "expected call")
         self.assertEqual(
             mock_requests.last_request.qs,
             {
                 "data_source_uuid": ["some_uuid"],
                 "external_id": ["custom_filter"],
-                "page": ["5"],
                 "per_page": ["12"],
             },
         )
         self.assertEqual(mock_requests.last_request.text, None)
         self.assertEqual(str(plan), str(expected))
 
-    @requests_mock.mock()
-    def test_cursor_list_plans_new_pagination(self, mock_requests):
-        expected_plan_dict = {
-            "uuid": "whatever_uuid",
-            "data_source_uuid": "some_uuid",
-            "name": "some plan",
-            "interval_count": 2,
-            "interval_unit": "moonshines",
-            "external_id": "custom_filter",
-        }
-        mock_requests.register_uri(
-            "GET",
-            (
-                "https://api.chartmogul.com/v1/plans?cursor=cursor=="
-                "&per_page=12&data_source_uuid=some_uuid&external_id=custom_filter"
-            ),
-            request_headers={"Authorization": "Basic dG9rZW46"},
-            status_code=200,
-            json={"plans": [expected_plan_dict], "has_more": True, "cursor": "cursor=="},
-        )
-        config = Config("token")  # is actually checked in mock
-        plan = Plan.all(
-            config,
-            cursor="cursor==",
-            per_page=12,
-            data_source_uuid="some_uuid",
-            external_id="custom_filter",
-        ).get()
-        expected = Plan._many([Plan(**expected_plan_dict)], has_more=True, cursor="cursor==")
-        self.assertEqual(str(plan), str(expected))
-
     @requests_mock.mock()
     def test_modify_plan(self, mock_requests):
         expected_plan_dict = {
diff --git a/test/api/test_plan_group.py b/test/api/test_plan_group.py
index fab5511..982cd45 100644
--- a/test/api/test_plan_group.py
+++ b/test/api/test_plan_group.py
@@ -66,7 +66,7 @@ def test_retrieve_plan_group(self, mock_requests):
         self.assertEqual(result.plans_count, 2)
 
     @requests_mock.mock()
-    def test_retrieve_plan_group_plans_old_pagination(self, mock_requests):
+    def test_retrieve_plan_group_plans(self, mock_requests):
         expected_plans = {
             "plans": [
                 {
@@ -86,51 +86,8 @@ def test_retrieve_plan_group_plans_old_pagination(self, mock_requests):
                     "external_id": "plan_EOsEG3pyySMBEP",
                 },
             ],
-            "current_page": 1,
-            "total_pages": 1,
-        }
-        mock_requests.register_uri(
-            "GET",
-            "https://api.chartmogul.com/v1/plan_groups/whatever_uuid/plans",
-            request_headers={"Authorization": "Basic dG9rZW46"},
-            status_code=200,
-            json=expected_plans,
-        )
-
-        config = Config("token")  # is actually checked in mock
-        result = PlanGroup.all(config, uuid="whatever_uuid").get()
-
-        self.assertEqual(mock_requests.call_count, 1, "expected call")
-        self.assertEqual(mock_requests.last_request.qs, {})
-        self.assertEqual(result.plans[0].uuid, "pl_cef31082-37be-11ea-a7bc-cb55fa0afcbb")
-        self.assertEqual(result.plans[1].uuid, "pl_cef46630-37be-11ea-a7bc-a316cc9407e9")
-        self.assertEqual(len(result.plans), 2)
-        self.assertEqual(result.total_pages, 1)
-        self.assertEqual(result.current_page, 1)
-
-    @requests_mock.mock()
-    def test_retrieve_plan_group_plans_new_pagination(self, mock_requests):
-        expected_plans = {
-            "plans": [
-                {
-                    "name": "Berghain Flatrate Pack - bi-annual",
-                    "uuid": "pl_cef31082-37be-11ea-a7bc-cb55fa0afcbb",
-                    "data_source_uuid": "ds_73c24b7e-37be-11ea-85a4-03a4322daccc",
-                    "interval_count": 6,
-                    "interval_unit": "month",
-                    "external_id": "plan_EOwj9vInDKILy1",
-                },
-                {
-                    "name": "Berghain Flatrate Pack - Skip the Queue Pack",
-                    "uuid": "pl_cef46630-37be-11ea-a7bc-a316cc9407e9",
-                    "data_source_uuid": "ds_73c24b7e-37be-11ea-85a4-03a4322daccc",
-                    "interval_count": 1,
-                    "interval_unit": "month",
-                    "external_id": "plan_EOsEG3pyySMBEP",
-                },
-            ],
-            "has_more": False,
             "cursor": "cursor==",
+            "has_more": False,
         }
         mock_requests.register_uri(
             "GET",
@@ -153,35 +110,6 @@ def test_retrieve_plan_group_plans_new_pagination(self, mock_requests):
 
     @requests_mock.mock()
     def test_all_plan_groups_old_pagination(self, mock_requests):
-        expected_plan_groups = {
-            "plan_groups": [
-                {"uuid": "whatever_uuid", "name": "good_plan", "plans_count": 2},
-                {"uuid": "my_uuid", "name": "best_plan", "plans_count": 5},
-            ],
-            "current_page": 1,
-            "total_pages": 1,
-        }
-        mock_requests.register_uri(
-            "GET",
-            "https://api.chartmogul.com/v1/plan_groups",
-            status_code=200,
-            json=expected_plan_groups,
-        )
-
-        config = Config("token")
-        result = PlanGroup.all(config).get()
-
-        self.assertEqual(mock_requests.call_count, 1, "expected call")
-        self.assertEqual(mock_requests.last_request.qs, {})
-        self.assertEqual(mock_requests.last_request.text, None)
-        self.assertTrue(isinstance(result.plan_groups[0], PlanGroup))
-        self.assertEqual(result.plan_groups[0].uuid, "whatever_uuid")
-        self.assertEqual(result.plan_groups[1].uuid, "my_uuid")
-        self.assertEqual(result.total_pages, 1)
-        self.assertEqual(result.current_page, 1)
-
-    @requests_mock.mock()
-    def test_all_plan_groups_new_pagination(self, mock_requests):
         expected_plan_groups = {
             "plan_groups": [
                 {"uuid": "whatever_uuid", "name": "good_plan", "plans_count": 2},
@@ -212,7 +140,9 @@ def test_all_plan_groups_new_pagination(self, mock_requests):
     @requests_mock.mock()
     def test_destroy_plan_group(self, mock_requests):
         mock_requests.register_uri(
-            "DELETE", "https://api.chartmogul.com/v1/plan_groups/my_uuid", status_code=204
+            "DELETE",
+            "https://api.chartmogul.com/v1/plan_groups/my_uuid",
+            status_code=204,
         )
 
         config = Config("token")
@@ -225,7 +155,11 @@ def test_destroy_plan_group(self, mock_requests):
 
     @requests_mock.mock()
     def test_modify_plan_group_name(self, mock_requests):
-        expected_plan_group_dict = {"uuid": "whatever_uuid", "name": "new_name", "plans_count": 2}
+        expected_plan_group_dict = {
+            "uuid": "whatever_uuid",
+            "name": "new_name",
+            "plans_count": 2,
+        }
         mock_requests.register_uri(
             "PATCH",
             "https://api.chartmogul.com/v1/plan_groups/whatever_uuid",
@@ -245,7 +179,11 @@ def test_modify_plan_group_name(self, mock_requests):
 
     @requests_mock.mock()
     def test_modify_plan_group_plans(self, mock_requests):
-        expected_plan_group_dict = {"uuid": "whatever_uuid", "name": "new_name", "plans_count": 3}
+        expected_plan_group_dict = {
+            "uuid": "whatever_uuid",
+            "name": "new_name",
+            "plans_count": 3,
+        }
         mock_requests.register_uri(
             "PATCH",
             "https://api.chartmogul.com/v1/plan_groups/whatever_uuid",
@@ -255,7 +193,9 @@ def test_modify_plan_group_plans(self, mock_requests):
         )
         config = Config("token")  # is actually checked in mock
         result = PlanGroup.modify(
-            config, uuid="whatever_uuid", data={"plans": "[pl_uuid_1, pl_uuid_2, pl_uuid_3]"}
+            config,
+            uuid="whatever_uuid",
+            data={"plans": "[pl_uuid_1, pl_uuid_2, pl_uuid_3]"},
         ).get()
 
         self.assertEqual(mock_requests.call_count, 1, "expected call")
diff --git a/test/api/test_subscription_event.py b/test/api/test_subscription_event.py
index 356f32f..713b02f 100644
--- a/test/api/test_subscription_event.py
+++ b/test/api/test_subscription_event.py
@@ -23,32 +23,7 @@
     "amount_in_cents": 1000,
 }
 
-sub_ev_list_expected_old = {
-    "subscription_events": [
-        {
-            "id": 7654321,
-            "external_id": "evnt_026",
-            "customer_external_id": "scus_022",
-            "data_source_uuid": "ds_1fm3eaac-62d0-31ec-clf4-4bf0mbe81aba",
-            "event_type": "subscription_start_scheduled",
-            "event_date": "2022-03-30 23:00:00.000",
-            "effective_date": "2022-04-01 23:00:00.000",
-            "subscription_external_id": "sub_0001",
-            "plan_external_id": "gol d_monthly",
-            "currency": "USD",
-            "amount_in_cents": 1000,
-        }
-    ],
-    "meta": {
-        "next_key": 67048503,
-        "prev_key": None,
-        "before_key": "2022-04-10T22:27:35.834Z",
-        "page": 1,
-        "total_pages": 166,
-    },
-}
-
-sub_ev_list_expected_new = {
+sub_ev_list_expected = {
     "subscription_events": [
         {
             "id": 7654321,
@@ -221,27 +196,20 @@ def test_modify_subscription_event_with_bad_params(self, mock_requests):
             self.fail("ArgumentMissingError not raised")
 
     @requests_mock.mock()
-    def test_all_subscription_events_old_pagination(self, mock_requests):
+    def test_all_subscription_events(self, mock_requests):
         mock_requests.register_uri(
             "GET",
             "https://api.chartmogul.com/v1/subscription_events",
             request_headers={"Authorization": "Basic dG9rZW46"},
             status_code=200,
-            json=sub_ev_list_expected_old,
+            json=sub_ev_list_expected,
         )
 
         config = Config("token")
         subscription_events = SubscriptionEvent.all(config).get()
 
         expected = SubscriptionEvent._many(
-            subscription_events=[sub_ev_one],
-            meta={
-                "next_key": 67048503,
-                "prev_key": None,
-                "before_key": "2022-04-10T22:27:35.834Z",
-                "page": 1,
-                "total_pages": 166,
-            },
+            subscription_events=[sub_ev_one], has_more=True, cursor="cursor=="
         )
 
         self.assertEqual(mock_requests.call_count, 1, "expected call")
@@ -262,7 +230,7 @@ def test_all_subscription_events_with_filters(self, mock_requests):
             "&customer_external_id=scus_022&event_type=subscription_start_scheduled&plan_external_id=gol d_monthly",
             request_headers={"Authorization": "Basic dG9rZW46"},
             status_code=200,
-            json=sub_ev_list_expected_new,
+            json=sub_ev_list_expected,
         )
 
         config = Config("token")
diff --git a/test/integration/fixtures/delete_invoice.yaml b/test/integration/fixtures/delete_invoice.yaml
index b1311e0..8949150 100644
--- a/test/integration/fixtures/delete_invoice.yaml
+++ b/test/integration/fixtures/delete_invoice.yaml
@@ -11,7 +11,7 @@ interactions:
       Content-Length:
       - '2'
       User-Agent:
-      - chartmogul-python/3.1.1
+      - chartmogul-python/4.0.0
       content-type:
       - application/json
     method: POST
diff --git a/test/integration/fixtures/fetch_subscription_events.yaml b/test/integration/fixtures/fetch_subscription_events.yaml
deleted file mode 100644
index 57e6f1c..0000000
--- a/test/integration/fixtures/fetch_subscription_events.yaml
+++ /dev/null
@@ -1,78 +0,0 @@
-interactions:
-- request:
-    body: null
-    headers:
-      Accept:
-      - '*/*'
-      Accept-Encoding:
-      - gzip, deflate
-      Connection:
-      - keep-alive
-      User-Agent:
-      - chartmogul-python/3.1.1
-      content-type:
-      - application/json
-    method: GET
-    uri: https://api.chartmogul.com/v1/subscription_events
-  response:
-    body:
-      string: !!binary |
-        H4sIAAAAAAAAA+2b35KiOBTG34Xrdir/Q3yOvtqtKQohqCBIQ7B1uvrdNwlbu+vUjoyEgF1llTfK
-        IR6Sn19OPpOPoO02bdLsa7U/VpE8yUq1wfrPj2CfBmtMuUAhJuglSGMVR+2xaxIZdZ25GKRtJDDM
-        oIjRKuFptoJQpquNhGKVbTiPM0bTOBXBS5B0rTqWsonkWcmmig+RbYBDATjU169yaKW6jqu6w+Gn
-        mOt2ENn94Fi3Ux9i/Qz//Y7+XvtYkX4EqdNGAOEVoCvIXwFbI7BG/A99r8wymaj9Sf4cB/ArAGv7
-        snGmiyJ1qU1bV4kncZXIw0GmprX/SaJpjo3u249P3SGN1MmkUax+nVBXm4Rvx7x1caX26hKs+wdN
-        uqaRVfLP+7g8djrbfRUl/cD2YSo+R7+41EjVxIn53r7TzECZmz5frpGAfpCAIQPMDOVVz96PRFGU
-        bcifSJjf3lxIAD9IIEghYO5I5Hm2u7TjkWCPphI2oQGVsDGLqQQWfpAgVCAKJkCCKtbsvCGBZp84
-        vgASoR8kYIi40XvHeWP7g2EXkaC3RWJ+ImxCAyJhY5YTCe6HCIY4Qab6dEUiqbdnh+ryiYRZUfSF
-        529Wl5j5QYIjxqeYNzhP6109ft4gj6YSNqEBlbAxy6kE9YMEo1QLhbtK7JqShrk3JOZfg34BJIgf
-        JCAmHLkTQRBNqst4IvBtkZifCJvQgEjYmOVEAvshgmGO8ASuBKXFJjH20Eij6onE/aUE8oQEAeEU
-        SOTVe/ZGxiOBHk0lbEIDKmFjllMJT94l1j4VN0PpuOAg7yxNHUqJJxL3q4Qn75ICqN1LdyQyFjIU
-        jlcJ+GgqYRMaUAkbs5hKIE9GFcOE4AmQwOWZnR1qiQEk5neqvgASnmwJhqmAEzhVOS7etg4qAW6r
-        xPxI2IQGVMLGLKcSnmwJHGIAzVA61hL5e1kIB6fqicTdtQTyZEtgbVXhCcrLrMhFqUbXElA8mEr0
-        Cd1WiT5mOZXw5EsQvTmHTYBEiMTu/YmE3mU0224JhPz4EgTyMJxgt0SYqdNl/MQBw6dK3PuvF/Lk
-        S1COw3AKlci3SJl2xrmXQ0jMbmj3CQ1MHJbj5SYOj76EmOI/jktZoScSc04c0JMvATEXdIIVx1Zl
-        SZaPV4lH24wLbUIDKmFjFlMJ6GkHDSGCsAmQwLu3fONQSzyRuHsRCj2tOLShjRnQv25HX6LYZCfq
-        oBKPthkX/sbOyz5mOZXwteIQIgQTuJe4oBfssAgdQGJ29/Ihkfj+EpRSxfoUSlDpMypRIfVZkb+P
-        +UANSN3IU/9hv2FvI7NjI/tP/j05I14hXgO8JvgbR9YPquOtPg+jFzDqqPTxHvNWL38I4p+ffwES
-        uS0yYzQAAA==
-    headers:
-      Access-Control-Allow-Credentials:
-      - 'true'
-      Cache-Control:
-      - max-age=0, private, must-revalidate
-      Connection:
-      - keep-alive
-      Content-Encoding:
-      - gzip
-      Content-Length:
-      - '1033'
-      Content-Type:
-      - application/json; charset=utf-8
-      Date:
-      - Fri, 19 May 2023 13:03:43 GMT
-      ETag:
-      - W/"605f65f25551e36f294b1276648844b4"
-      Referrer-Policy:
-      - strict-origin-when-cross-origin
-      Vary:
-      - Accept-Encoding
-      - Accept-Encoding
-      X-Content-Type-Options:
-      - nosniff
-      X-Download-Options:
-      - noopen
-      X-Frame-Options:
-      - DENY
-      X-Permitted-Cross-Domain-Policies:
-      - none
-      X-Request-Id:
-      - 4549e2f044e141372f3e09f1bf571314
-      X-Runtime:
-      - '0.052033'
-      X-XSS-Protection:
-      - 1; mode=block
-    status:
-      code: 200
-      message: OK
-version: 1
diff --git a/test/integration/test_fetch_account.py b/test/integration/test_fetch_account.py
new file mode 100644
index 0000000..5088493
--- /dev/null
+++ b/test/integration/test_fetch_account.py
@@ -0,0 +1,16 @@
+import unittest
+import vcr
+from chartmogul import Config, Account
+
+config = Config(api_key="-")
+
+
+class FetchAccountTestCase(unittest.TestCase):
+    """
+    Tests errors & user mistakes.
+    """
+
+    @vcr.use_cassette("fixtures/fetch_account.yaml", filter_headers=["authorization"], record=True)
+    def test_fetch_account(self):
+        account = Account.retrieve(config).get()
+        self.assertTrue(isinstance(account, Account))
diff --git a/test/integration/test_fetch_subscription_events.py b/test/integration/test_fetch_subscription_events.py
deleted file mode 100644
index cad28ee..0000000
--- a/test/integration/test_fetch_subscription_events.py
+++ /dev/null
@@ -1,15 +0,0 @@
-import unittest
-import vcr
-from chartmogul import Config, SubscriptionEvent
-
-config = Config(api_key="-")
-
-
-class FetchSubscriptionEventsTestCase(unittest.TestCase):
-    """
-    Tests errors & user mistakes.
-    """
-
-    @vcr.use_cassette("fixtures/fetch_subscription_events.yaml", filter_headers=["authorization"])
-    def test_subscription_events(self):
-        result = SubscriptionEvent.all(config).get()