Typeguard

- Fixed handling of ``typing_extensions.Literal`` on Python 3.8 and 3.9 when
``typing_extensions>=4.6.0`` is installed
(`363 <https://github.com/agronholm/typeguard/issues/363>`_; PR by Alex Waygood)
- Fixed ``NameError`` when generated type checking code references an imported name from
a method (`362 <https://github.com/agronholm/typeguard/issues/362>`_)
- Fixed docstrings disappearing from instrumented functions
(`359 <https://github.com/agronholm/typeguard/issues/359>`_)
- Fixed ``typechecked`` failing to instrument functions when there are more than one
function within the same scope
(`355 <https://github.com/agronholm/typeguard/issues/355>`_)
- Fixed ``frozenset`` not being checked
(`367 <https://github.com/agronholm/typeguard/issues/367>`_)

- No changes

- Fixed ``typechecked`` optimization causing compilation of instrumented code to fail
when an ``if`` block was left empty by the AST transformer
(`352 <https://github.com/agronholm/typeguard/issues/352>`_)
- Fixed the AST transformer trying to parse the second argument of ``typing.Annotated``
as a forward reference (`353 <https://github.com/agronholm/typeguard/issues/353>`_)

- Added ``InstrumentationWarning`` to the public API
- Changed ``typechecked`` to skip instrumentation in optimized mode, as in typeguard
2.x
- Avoid type checks where the types in question are shadowed by local variables
- Fixed instrumentation using ``typing.Optional`` without a subscript when the subscript
value was erased due to being an ignored import
- Fixed ``TypeError: isinstance() arg 2 must be a type or tuple of types`` when
instrumented code tries to check a value against a naked (``str``, not ``ForwardRef``)
forward reference
- Fixed instrumentation using the wrong "self" type in the ``__new__()`` method

- Fixed imports guarded by ``if TYPE_CHECKING:`` when used with subscripts
(``SomeType[...]``) being replaced with ``Any[...]`` instead of just ``Any``
- Fixed instrumentation inadvertently mutating a function's annotations on Python 3.7
and 3.8
- Fixed ``Concatenate[...]`` in ``Callable`` parameters causing ``TypeError`` to be
raised
- Fixed type checks for ``*args`` or ``**kwargs`` not being suppressed when their types
are unusable (guarded by ``if TYPE_CHECKING:`` or otherwise)
- Fixed ``TypeError`` when checking against a generic ``NewType``
- Don't try to check types shadowed by argument names (e.g.
``def foo(x: type, type: str): ...``)
- Don't check against unions where one of the elements is ``Any``

- Fixed ``typing.Literal`` subscript contents being evaluated as forward references
- Fixed resolution of forward references in type aliases