It is now possible to construct a :class:`~pytest.MonkeyPatch` object directly as ``pytest.MonkeyPatch()``,
in cases when the :fixture:`monkeypatch` fixture cannot be used. Previously some users imported it
from the private `_pytest.monkeypatch.MonkeyPatch` namespace.

Additionally, :meth:`MonkeyPatch.context <pytest.MonkeyPatch.context>` is now a classmethod,
and can be used as ``with MonkeyPatch.context() as mp: ...``. This is the recommended way to use
``MonkeyPatch`` directly, since unlike the ``monkeypatch`` fixture, an instance created directly
is not ``undo()``-ed automatically.