Remove third_party/3/enum.py (#2563)

All Python 3 versions supported by typeshed (3.4+) have enum as part
of the standard library.

Make the third-party Python 2 version consistent with the Python 3 version.

third_party/2/enum.pyi

@@ -1,4 +1,6 @@
-from typing import List, Any, TypeVar, Union, Iterable, Iterator, TypeVar, Generic, Type, Sized, Reversible, Container, Mapping
+# NB: third_party/2/enum.pyi and stdlib/3.4/enum.pyi must remain consistent!
+import sys
+from typing import Any, Iterator, List, Mapping, Type, TypeVar, Union
 from abc import ABCMeta
 
 _T = TypeVar('_T')
@@ -34,3 +36,30 @@ class IntEnum(int, Enum):
     value = ...  # type: int
 
 def unique(enumeration: _S) -> _S: ...
+
+if sys.version_info >= (3, 6):
+    _auto_null = ...  # type: Any
+
+    # subclassing IntFlag so it picks up all implemented base functions, best modeling behavior of enum.auto()
+    class auto(IntFlag):
+        value = ...  # type: Any
+
+    class Flag(Enum):
+        def __contains__(self: _T, other: _T) -> bool: ...
+        def __repr__(self) -> str: ...
+        def __str__(self) -> str: ...
+        def __bool__(self) -> bool: ...
+        def __or__(self: _T, other: _T) -> _T: ...
+        def __and__(self: _T, other: _T) -> _T: ...
+        def __xor__(self: _T, other: _T) -> _T: ...
+        def __invert__(self: _T) -> _T: ...
+
+    # The `type: ignore` comment is needed because mypy considers the type
+    # signatures of several methods defined in int and Flag to be incompatible.
+    class IntFlag(int, Flag):  # type: ignore
+        def __or__(self: _T, other: Union[int, _T]) -> _T: ...
+        def __and__(self: _T, other: Union[int, _T]) -> _T: ...
+        def __xor__(self: _T, other: Union[int, _T]) -> _T: ...
+        __ror__ = __or__
+        __rand__ = __and__
+        __rxor__ = __xor__

third_party/3/enum.pyi

@@ -1,65 +0,0 @@
-# NB: third_party/3/enum.pyi and stdlib/3.4/enum.pyi must remain consistent!
-import sys
-from typing import Any, Iterator, List, Mapping, Type, TypeVar, Union
-from abc import ABCMeta
-
-_T = TypeVar('_T')
-_S = TypeVar('_S', bound=Type[Enum])
-
-# Note: EnumMeta actually subclasses type directly, not ABCMeta.
-# This is a temporary workaround to allow multiple creation of enums with builtins
-# such as str as mixins, which due to the handling of ABCs of builtin types, cause
-# spurious inconsistent metaclass structure. See #1595.
-# Structurally: Iterable[T], Reversible[T], Container[T] where T is the enum itself
-class EnumMeta(ABCMeta):
-    def __iter__(self: Type[_T]) -> Iterator[_T]: ...
-    def __reversed__(self: Type[_T]) -> Iterator[_T]: ...
-    def __contains__(self: Type[_T], member: object) -> bool: ...
-    def __getitem__(self: Type[_T], name: str) -> _T: ...
-    @property
-    def __members__(self: Type[_T]) -> Mapping[str, _T]: ...
-    def __len__(self) -> int: ...
-
-class Enum(metaclass=EnumMeta):
-    def __new__(cls: Type[_T], value: object) -> _T: ...
-    def __repr__(self) -> str: ...
-    def __str__(self) -> str: ...
-    def __dir__(self) -> List[str]: ...
-    def __format__(self, format_spec: str) -> str: ...
-    def __hash__(self) -> Any: ...
-    def __reduce_ex__(self, proto: object) -> Any: ...
-
-    name = ...  # type: str
-    value = ...  # type: Any
-
-class IntEnum(int, Enum):
-    value = ...  # type: int
-
-def unique(enumeration: _S) -> _S: ...
-
-if sys.version_info >= (3, 6):
-    _auto_null = ...  # type: Any
-
-    # subclassing IntFlag so it picks up all implemented base functions, best modeling behavior of enum.auto()
-    class auto(IntFlag):
-        value = ...  # type: Any
-
-    class Flag(Enum):
-        def __contains__(self: _T, other: _T) -> bool: ...
-        def __repr__(self) -> str: ...
-        def __str__(self) -> str: ...
-        def __bool__(self) -> bool: ...
-        def __or__(self: _T, other: _T) -> _T: ...
-        def __and__(self: _T, other: _T) -> _T: ...
-        def __xor__(self: _T, other: _T) -> _T: ...
-        def __invert__(self: _T) -> _T: ...
-
-    # The `type: ignore` comment is needed because mypy considers the type
-    # signatures of several methods defined in int and Flag to be incompatible.
-    class IntFlag(int, Flag):  # type: ignore
-        def __or__(self: _T, other: Union[int, _T]) -> _T: ...
-        def __and__(self: _T, other: Union[int, _T]) -> _T: ...
-        def __xor__(self: _T, other: Union[int, _T]) -> _T: ...
-        __ror__ = __or__
-        __rand__ = __and__
-        __rxor__ = __xor__