Fix a regression in 2.13.2 where a RunTimeError could be raised unexpectedly.

Closes #1958

Fix overwritten attributes in inherited dataclasses not being ordered correctly.

Closes pylint-dev/pylint#7881

Fix a false positive when an attribute named Enum was confused with enum.Enum.
Calls to Enum are now inferred & the qualified name is checked.

Refs pylint-dev/pylint#5719

Removed version conditions on typing_extensions dependency. Removed typing_extensions from
our tests requirements as it was preventing issues to appear in our continuous integration.

Closes #1945

Bumping typing_extensions to 4.0.0 that is required when using Self

Closes #1942

Fixed importing of modules that have the same name as the file that is importing.
astroid will now correctly handle an import math statement in a file called math.py
by relying on the import system.

Refs pylint-dev/pylint#5151

Create ContextManagerModel and let GeneratorModel inherit from it.

Refs pylint-dev/pylint#2567

Added a regex brain.

Refs pylint-dev/pylint#1911

Support "is None" constraints from if statements during inference.

Refs #791
Refs pylint-dev/pylint#157
Refs pylint-dev/pylint#1472
Refs pylint-dev/pylint#2016
Refs pylint-dev/pylint#2631
Refs pylint-dev/pylint#2880

Handle the effect of properties on the __init__ of a dataclass correctly.

Closes pylint-dev/pylint#5225

Handle the effect of kw_only=True in dataclass fields correctly.

Closes pylint-dev/pylint#7623

Handle the effect of init=False in dataclass fields correctly.

Closes pylint-dev/pylint#7291

Fix crash if numpy module doesn't have version attribute.

Refs pylint-dev/pylint#7868

Handle AttributeError during str.format template inference tip evaluation

Closes pylint-dev/pylint#1902

Prevent returning an empty list for ClassDef.slots() when the mro list contains one class & it is not object.

Refs pylint-dev/pylint#5099

Prevent a crash when inferring calls to str.format with inferred arguments
that would be invalid.

Closes #1856

Infer the length argument of the random.sample function.

Refs pylint-dev/pylint#7706

Catch ValueError when indexing some builtin containers and sequences during inference.

Closes #1843