Fix conditional imports within collections (#5040)

Co-authored-by: Eric Traut <[email protected]>

Author: erictraut

stdlib/collections/__init__.pyi

@@ -1,9 +1,22 @@
 import sys
-import typing
 from typing import Any, Dict, Generic, List, Optional, Tuple, Type, TypeVar, Union, overload
 
 if sys.version_info < (3, 10):
     from _collections_abc import *
+else:
+    from typing import (
+        Callable,
+        ItemsView,
+        Iterable,
+        Iterator,
+        KeysView,
+        Mapping,
+        MutableMapping,
+        MutableSequence,
+        Reversible,
+        Sequence,
+        ValuesView,
+    )
 
 _S = TypeVar("_S")
 _T = TypeVar("_T")
@@ -103,7 +116,7 @@ class UserString(Sequence[str]):
     def center(self: _UserStringT, width: int, *args: Any) -> _UserStringT: ...
     def count(self, sub: Union[str, UserString], start: int = ..., end: int = ...) -> int: ...
     if sys.version_info >= (3, 8):
-        def encode(self: _UserStringT, encoding: Optional[str] = ..., errors: Optional[str] = ...) -> bytes: ...
+        def encode(self: UserString, encoding: Optional[str] = ..., errors: Optional[str] = ...) -> bytes: ...
     else:
         def encode(self: _UserStringT, encoding: Optional[str] = ..., errors: Optional[str] = ...) -> _UserStringT: ...
     def endswith(self, suffix: Union[str, Tuple[str, ...]], start: Optional[int] = ..., end: Optional[int] = ...) -> bool: ...
@@ -281,9 +294,9 @@ class ChainMap(MutableMapping[_KT, _VT], Generic[_KT, _VT]):
     def __init__(self, *maps: Mapping[_KT, _VT]) -> None: ...
     @property
     def maps(self) -> List[Mapping[_KT, _VT]]: ...
-    def new_child(self, m: Mapping[_KT, _VT] = ...) -> typing.ChainMap[_KT, _VT]: ...
+    def new_child(self, m: Mapping[_KT, _VT] = ...) -> ChainMap[_KT, _VT]: ...
     @property
-    def parents(self) -> typing.ChainMap[_KT, _VT]: ...
+    def parents(self) -> ChainMap[_KT, _VT]: ...
     def __setitem__(self, k: _KT, v: _VT) -> None: ...
     def __delitem__(self, v: _KT) -> None: ...
     def __getitem__(self, k: _KT) -> _VT: ...