Remove compatibility for IsADirectoryError PermissionError NotADirectoryError

jedi/_compatibility.py

@@ -216,23 +216,6 @@ try:
 except ImportError:
     from itertools import izip_longest as zip_longest  # Python 2  # noqa: F401
 
-try:
-    IsADirectoryError = IsADirectoryError
-except NameError:
-    IsADirectoryError = IOError
-
-try:
-    PermissionError = PermissionError
-except NameError:
-    PermissionError = IOError
-
-try:
-    NotADirectoryError = NotADirectoryError
-except NameError:
-    class NotADirectoryError(Exception):
-        # Don't implement this for Python 2 anymore.
-        pass
-
 
 def utf8_repr(func):
     """

jedi/api/project.py

@@ -12,8 +12,6 @@ import errno
 import json
 import sys
 
-from jedi._compatibility import PermissionError, \
-    IsADirectoryError, NotADirectoryError
 from jedi import debug
 from jedi.api.environment import get_cached_default_environment, create_environment
 from jedi.api.exceptions import WrongVersion