diff --git a/README.md b/README.md
index 85f2c54..6c04d98 100644
--- a/README.md
+++ b/README.md
@@ -8,10 +8,15 @@
 
 ## Description
 
-A Warmup Scheduler for Pytorch to achieve the warmup learning rate at the beginning of training.
+A Warmup Scheduler for Pytorch to make the warmup learning rate change at the beginning of training.
 
 ## setup
 
+Notice: need to install pytorch>=1.1.0 manually. \
+The official website of pytorch is: https://pytorch.org/
+
+Then install as follows:
+
 ```
 pip install warmup_scheduler_pytorch
 ```
@@ -26,7 +31,7 @@ import torch
 from torch.optim import SGD  # example
 from torch.optim.lr_scheduler import CosineAnnealingLR  # example
 
-from warmup_scheduler_pytorch.warmup_module import WarmUpScheduler
+from warmup_scheduler_pytorch import WarmUpScheduler
 
 model = Model()
 optimizer = SGD(model.parameters(), lr=0.1)
diff --git a/example.py b/example.py
index ca44c63..141193b 100644
--- a/example.py
+++ b/example.py
@@ -45,7 +45,7 @@ def run():
                 epoch_lr[1].append(get_lr(optimizer))
 
             # output = model(...)
-            # loss = loss_fn(output, ...)
+            # loss = loss_fn(output, label)
             # loss.backward()
             optimizer.step()
             optimizer.zero_grad()
diff --git a/pyproject.toml b/pyproject.toml
index fa7093a..04d1b04 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,3 @@
 [build-system]
-requires = ["setuptools>=42"]
+requires = ["setuptools>=42.0.0"]
 build-backend = "setuptools.build_meta"
\ No newline at end of file
diff --git a/setup.cfg b/setup.cfg
index e577714..5a748ad 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -13,7 +13,10 @@ classifiers =
     Intended Audience :: Science/Research
     License :: OSI Approved :: MIT License
     Operating System :: OS Independent
-    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
     Topic :: Scientific/Engineering :: Artificial Intelligence
 
 
@@ -22,8 +25,8 @@ package_dir =
     = src
 packages = find:
 python_requires = >=3.6
-install_requires=
-    torch >= 1.7.1
+# install_requires=
+#     torch >= 1.1.0
 
 
 [options.packages.find]
diff --git a/src/warmup_scheduler_pytorch/__init__.py b/src/warmup_scheduler_pytorch/__init__.py
index 99aef39..266584d 100644
--- a/src/warmup_scheduler_pytorch/__init__.py
+++ b/src/warmup_scheduler_pytorch/__init__.py
@@ -1,6 +1,5 @@
 from .warmup_module import WarmUpScheduler, VERSION
 
-__all__ = ['__version__', 'WarmUpScheduler']
-
 __version__ = VERSION
 
+__all__ = ['__version__', 'WarmUpScheduler']
diff --git a/src/warmup_scheduler_pytorch/warmup_module.py b/src/warmup_scheduler_pytorch/warmup_module.py
index ec917db..b8e4b72 100644
--- a/src/warmup_scheduler_pytorch/warmup_module.py
+++ b/src/warmup_scheduler_pytorch/warmup_module.py
@@ -4,11 +4,11 @@
 """
 
 from torch.optim import Optimizer
-from torch.optim.lr_scheduler import _LRScheduler  # ignore its error
+from torch.optim.lr_scheduler import _LRScheduler
 
 __all__ = ['VERSION', 'WarmUpScheduler']
 
-VERSION = '0.1.0'
+VERSION = '0.1.1'
 
 
 class WarmUpScheduler(object):
diff --git a/tests/test_base.py b/tests/test_base.py
index cac8b6f..0fe325b 100644
--- a/tests/test_base.py
+++ b/tests/test_base.py
@@ -1,10 +1,3 @@
-from src.warmup_scheduler_pytorch import WarmUpScheduler, __version__
-from src.warmup_scheduler_pytorch.warmup_module import VERSION
-
-
-def test_version():
-    assert VERSION == __version__
-
-
 def test_import():
-    assert isinstance(WarmUpScheduler, object)
+    from src.warmup_scheduler_pytorch import WarmUpScheduler, __version__
+    from src.warmup_scheduler_pytorch.warmup_module import VERSION
diff --git a/tests/test_warmup.py b/tests/test_warmup.py
index 0b78ae6..e6e022d 100644
--- a/tests/test_warmup.py
+++ b/tests/test_warmup.py
@@ -77,8 +77,8 @@ def test_warmup_init(self):
             pass
 
     def test_warmup_state_dict(self):
-        sd = self.warmup_scheduler.state_dict()
-        self.warmup_scheduler.load_state_dict(sd)
+        state_dict = self.warmup_scheduler.state_dict()
+        self.warmup_scheduler.load_state_dict(state_dict)
 
     def test_warmup_get(self):
         self.warmup_scheduler.get_last_lr()