Remove chemistry dep warning (#4466)

* Remove chemistry dep warning

* Fix changelog

* style: pre-commit fixes

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -4,7 +4,8 @@
 
 - Added sensitivity calculation support for `pybamm.Simulation` and `pybamm.Experiment` ([#4415](https://github.com/pybamm-team/PyBaMM/pull/4415))
 - Added OpenMP parallelization to IDAKLU solver for lists of input parameters ([#4449](https://github.com/pybamm-team/PyBaMM/pull/4449))
-- Added phase-dependent particle options to LAM #4369
+- Added phase-dependent particle options to LAM
+  ([#4369](https://github.com/pybamm-team/PyBaMM/pull/4369))
 - Added a lithium ion equivalent circuit model with split open circuit voltages for each electrode (`SplitOCVR`). ([#4330](https://github.com/pybamm-team/PyBaMM/pull/4330))
 
 ## Optimizations
@@ -18,6 +19,8 @@
 
 ## Breaking changes
 
+- Removed the deprecation warning for the chemistry argument in
+  ParameterValues ([#4466](https://github.com/pybamm-team/PyBaMM/pull/4466))
 - The parameters "... electrode OCP entropic change [V.K-1]" and "... electrode volume change" are now expected to be functions of stoichiometry only instead of functions of both stoichiometry and maximum concentration ([#4427](https://github.com/pybamm-team/PyBaMM/pull/4427))
 - Renamed `set_events` function to `add_events_from` to better reflect its purpose. ([#4421](https://github.com/pybamm-team/PyBaMM/pull/4421))
 

src/pybamm/parameters/parameter_values.py

@@ -35,15 +35,7 @@ class ParameterValues:
 
     """
 
-    def __init__(self, values, chemistry=None):
-        if chemistry is not None:
-            raise ValueError(
-                "The 'chemistry' keyword argument has been deprecated. "
-                "Call `ParameterValues` with a dictionary dictionary of "
-                "parameter values, or the name of a parameter set (string), "
-                "as the single argument, e.g. `ParameterValues('Chen2020')`.",
-            )
-
+    def __init__(self, values):
         # add physical constants as default values
         self._dict_items = pybamm.FuzzyDict(
             {

tests/unit/test_parameters/test_parameter_values.py

@@ -37,12 +37,6 @@ def test_init(self):
         param = pybamm.ParameterValues({"a": 1, "chemistry": "lithium-ion"})
         assert "chemistry" not in param.keys()
 
-        # chemistry kwarg removed
-        with pytest.raises(
-            ValueError, match="'chemistry' keyword argument has been deprecated"
-        ):
-            pybamm.ParameterValues(None, chemistry="lithium-ion")
-
         # junk param values rejected
         with pytest.raises(ValueError, match="'Junk' is not a valid parameter set."):
             pybamm.ParameterValues("Junk")