jsonschema

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In the following code PyCharm finds 1 warning and 1 error:

import jsonschema

v: jsonschema.protocols.Validator = jsonschema.Draft202012Validator({})
#                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#                                   Expected type 'Validator', got 'Draft202012Validator' instead
print(isinstance(jsonschema.Draft202012Validator({}), jsonschema.protocols.Validator))
#                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#       Only @runtime_checkable protocols can be used with instance and class checks

mypy finds them too:

test004.py:3: error: Incompatible types in assignment (expression has type "Draft202012Validator", variable has type "Validator")  [assignment]
test004.py:3: note: Following member(s) of "Draft202012Validator" have conflicts:
test004.py:3: note:     Expected:
test004.py:3: note:         def evolve(self, **kwargs: Any) -> Validator
test004.py:3: note:     Got:
test004.py:3: note:         def evolve(self, **changes: Any) -> _Validator
test004.py:3: note:     schema: expected "dict[Any, Any] | bool", got "bool | Mapping[str, Any]"
test004.py:6: error: Only @runtime_checkable protocols can be used with instance and class checks  [misc]
Found 2 errors in 1 file (checked 1 source file)

But the code works and prints "True".

Why doesn't Validator protocol work as expected? Is this jsonschema library issue? Or am I doing something wrong here (and if yes, how to do it correctly)?