Fix type annotations for glob (#1386)

Author: amstree

stdlib/2/glob.pyi

@@ -1,8 +1,6 @@
-from typing import List, Iterator, Union
+from typing import List, Iterator, Union, AnyStr
 
-_string = Union[str, unicode]
-
-def glob(pathname: _string) -> List[_string]: ...
-def iglob(pathname: _string) -> Iterator[_string]: ...
-def glob1(dirname: _string, pattern: _string) -> List[_string]: ...
-def glob0(dirname: _string, basename: _string) -> List[_string]: ...
+def glob(pathname: AnyStr) -> List[AnyStr]: ...
+def iglob(pathname: AnyStr) -> Iterator[AnyStr]: ...
+def glob1(dirname: Union[str, unicode], pattern: AnyStr) -> List[AnyStr]: ...
+def glob0(dirname: Union[str, unicode], basename: AnyStr) -> List[AnyStr]: ...