Reports invalid definition and usage of Enum.

Example:

from enum import Enum


class Shape(Enum):
    SQUARE = 1
    CIRCLE = 2


class ExtendedShape(Shape):  # Enum class 'Shape' is final and cannot be subclassed
    TRIANGLE = 3

from enum import Enum


class Color(Enum):
    _value_: int
    RED = 1
    GREEN = "green"  # Type 'str' is not assignable to declared type 'int'

from enum import Enum


class Pet(Enum):
    CAT = 1
    DOG: int = 2  # Type annotations are not allowed for enum members

from enum import Enum, unique


class Mixin:
    pass


class Color(Enum, Mixin):  # Enum class 'Enum' must be the last base class
    _red_ = 1  # The name '_red_' is reserved for future Enum use


@unique
class Size(Enum):
    SMALL = 1
    LITTLE = 1  # Unique enum member 'LITTLE' has the same value as 'SMALL'