diff --git a/stdlib/2/os/path.pyi b/stdlib/2/os/path.pyi
index bfd88a454622..7488956f2671 100644
--- a/stdlib/2/os/path.pyi
+++ b/stdlib/2/os/path.pyi
@@ -3,8 +3,14 @@
 
 # based on http://docs.python.org/3.2/library/os.path.html
 # adapted for 2.7 by Michal Pokorny
+import sys
+from typing import (
+    overload, List, Any, AnyStr, Sequence, Tuple, BinaryIO, TextIO,
+    TypeVar, Union, Text, Callable
+)
 
-from typing import overload, List, Any, Tuple, BinaryIO, TextIO, TypeVar, Callable, AnyStr
+_T = TypeVar('_T')
+_PathType = Union[bytes, Text]
 
 # ----- os.path variables -----
 supports_unicode_filenames = False
@@ -22,25 +28,32 @@ devnull = ...  # type: str
 def abspath(path: AnyStr) -> AnyStr: ...
 def basename(path: AnyStr) -> AnyStr: ...
 
-def commonprefix(list: List[AnyStr]) -> AnyStr: ...
+if sys.version_info >= (3, 5):
+    def commonpath(paths: Sequence[AnyStr]) -> AnyStr: ...
+
+# NOTE: Empty lists results in '' (str) regardless of contained type.
+# Also, in Python 2 mixed sequences of Text and bytes results in either Text or bytes
+# So, fall back to Any
+def commonprefix(list: Sequence[AnyStr]) -> Any: ...
+
 def dirname(path: AnyStr) -> AnyStr: ...
-def exists(path: unicode) -> bool: ...
-def lexists(path: unicode) -> bool: ...
+def exists(path: _PathType) -> bool: ...
+def lexists(path: _PathType) -> bool: ...
 def expanduser(path: AnyStr) -> AnyStr: ...
 def expandvars(path: AnyStr) -> AnyStr: ...
 
 # These return float if os.stat_float_times() == True,
 # but int is a subclass of float.
-def getatime(path: unicode) -> float: ...
-def getmtime(path: unicode) -> float: ...
-def getctime(path: unicode) -> float: ...
+def getatime(path: _PathType) -> float: ...
+def getmtime(path: _PathType) -> float: ...
+def getctime(path: _PathType) -> float: ...
 
-def getsize(path: unicode) -> int: ...
-def isabs(path: unicode) -> bool: ...
-def isfile(path: unicode) -> bool: ...
-def isdir(path: unicode) -> bool: ...
-def islink(path: unicode) -> bool: ...
-def ismount(path: unicode) -> bool: ...
+def getsize(path: _PathType) -> int: ...
+def isabs(path: _PathType) -> bool: ...
+def isfile(path: _PathType) -> bool: ...
+def isdir(path: _PathType) -> bool: ...
+def islink(path: _PathType) -> bool: ...
+def ismount(path: _PathType) -> bool: ...
 
 def join(path: AnyStr, *paths: AnyStr) -> AnyStr: ...
 
@@ -49,7 +62,7 @@ def normpath(path: AnyStr) -> AnyStr: ...
 def realpath(path: AnyStr) -> AnyStr: ...
 def relpath(path: AnyStr, start: AnyStr = ...) -> AnyStr: ...
 
-def samefile(path1: unicode, path2: unicode) -> bool: ...
+def samefile(path1: _PathType, path2: _PathType) -> bool: ...
 def sameopenfile(fp1: int, fp2: int) -> bool: ...
 # TODO
 # def samestat(stat1: stat_result,
@@ -61,5 +74,5 @@ def splitext(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...
 
 def splitunc(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...  # Windows only, deprecated
 
-_T = TypeVar('_T')
-def walk(path: AnyStr, visit: Callable[[_T, AnyStr, List[AnyStr]], Any], arg: _T) -> None: ...
+if sys.version_info < (3,):
+    def walk(path: AnyStr, visit: Callable[[_T, AnyStr, List[AnyStr]], Any], arg: _T) -> None: ...
diff --git a/stdlib/3/os/path.pyi b/stdlib/3/os/path.pyi
index c695c5738ac4..7488956f2671 100644
--- a/stdlib/3/os/path.pyi
+++ b/stdlib/3/os/path.pyi
@@ -2,9 +2,15 @@
 # Ron Murawski <ron@horizonchess.com>
 
 # based on http://docs.python.org/3.2/library/os.path.html
-
+# adapted for 2.7 by Michal Pokorny
 import sys
-from typing import overload, List, Any, AnyStr, Sequence, Tuple, BinaryIO, TextIO
+from typing import (
+    overload, List, Any, AnyStr, Sequence, Tuple, BinaryIO, TextIO,
+    TypeVar, Union, Text, Callable
+)
+
+_T = TypeVar('_T')
+_PathType = Union[bytes, Text]
 
 # ----- os.path variables -----
 supports_unicode_filenames = False
@@ -25,26 +31,29 @@ def basename(path: AnyStr) -> AnyStr: ...
 if sys.version_info >= (3, 5):
     def commonpath(paths: Sequence[AnyStr]) -> AnyStr: ...
 
-# NOTE: Empty List[bytes] results in '' (str) => fall back to Any return type.
-def commonprefix(list: List[AnyStr]) -> Any: ...
+# NOTE: Empty lists results in '' (str) regardless of contained type.
+# Also, in Python 2 mixed sequences of Text and bytes results in either Text or bytes
+# So, fall back to Any
+def commonprefix(list: Sequence[AnyStr]) -> Any: ...
+
 def dirname(path: AnyStr) -> AnyStr: ...
-def exists(path: AnyStr) -> bool: ...
-def lexists(path: AnyStr) -> bool: ...
+def exists(path: _PathType) -> bool: ...
+def lexists(path: _PathType) -> bool: ...
 def expanduser(path: AnyStr) -> AnyStr: ...
 def expandvars(path: AnyStr) -> AnyStr: ...
 
+# These return float if os.stat_float_times() == True,
+# but int is a subclass of float.
+def getatime(path: _PathType) -> float: ...
+def getmtime(path: _PathType) -> float: ...
+def getctime(path: _PathType) -> float: ...
 
-# These return float if os.stat_float_times() == True
-def getatime(path: AnyStr) -> Any: ...
-def getmtime(path: AnyStr) -> Any: ...
-def getctime(path: AnyStr) -> Any: ...
-
-def getsize(path: AnyStr) -> int: ...
-def isabs(path: AnyStr) -> bool: ...
-def isfile(path: AnyStr) -> bool: ...
-def isdir(path: AnyStr) -> bool: ...
-def islink(path: AnyStr) -> bool: ...
-def ismount(path: AnyStr) -> bool: ...
+def getsize(path: _PathType) -> int: ...
+def isabs(path: _PathType) -> bool: ...
+def isfile(path: _PathType) -> bool: ...
+def isdir(path: _PathType) -> bool: ...
+def islink(path: _PathType) -> bool: ...
+def ismount(path: _PathType) -> bool: ...
 
 def join(path: AnyStr, *paths: AnyStr) -> AnyStr: ...
 
@@ -53,8 +62,9 @@ def normpath(path: AnyStr) -> AnyStr: ...
 def realpath(path: AnyStr) -> AnyStr: ...
 def relpath(path: AnyStr, start: AnyStr = ...) -> AnyStr: ...
 
-def samefile(path1: AnyStr, path2: AnyStr) -> bool: ...
+def samefile(path1: _PathType, path2: _PathType) -> bool: ...
 def sameopenfile(fp1: int, fp2: int) -> bool: ...
+# TODO
 # def samestat(stat1: stat_result,
 #             stat2: stat_result) -> bool: ...  # Unix only
 
@@ -62,4 +72,7 @@ def split(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...
 def splitdrive(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...
 def splitext(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...
 
-# def splitunc(path: str) -> Tuple[str, str]: ...  # Windows only, deprecated
+def splitunc(path: AnyStr) -> Tuple[AnyStr, AnyStr]: ...  # Windows only, deprecated
+
+if sys.version_info < (3,):
+    def walk(path: AnyStr, visit: Callable[[_T, AnyStr, List[AnyStr]], Any], arg: _T) -> None: ...