readers: fix undefined FileNotFoundError and NotADirectoryError on Python 2

Signed-off-by: Filipe Laíns <[email protected]>

Author: FFY00

importlib_resources/_compat.py

@@ -36,6 +36,12 @@ class ABC(object):                                          # type: ignore
     FileNotFoundError = OSError                                 # type: ignore
 
 
+try:
+    NotADirectoryError = NotADirectoryError                       # type: ignore
+except NameError:
+    NotADirectoryError = OSError                                 # type: ignore
+
+
 try:
     from zipfile import Path as ZipPath  # type: ignore
 except ImportError:

importlib_resources/readers.py

@@ -5,6 +5,7 @@
 from . import abc
 
 from ._compat import Path, ZipPath
+from ._compat import FileNotFoundError, NotADirectoryError
 
 
 class FileReader(abc.TraversableResources):