Fix imports from collections.abc

Lib/test/test_collections.py

@@ -10,12 +10,13 @@
 import keyword
 import re
 import sys
-from collections import Hashable, Iterable, Iterator
-from collections import Sized, Container, Callable
-from collections import Set, MutableSet
-from collections import Mapping, MutableMapping, KeysView, ItemsView, UserDict
-from collections import Sequence, MutableSequence
-from collections import ByteString
+from collections import UserDict
+from collections.abc import Hashable, Iterable, Iterator
+from collections.abc import Sized, Container, Callable
+from collections.abc import Set, MutableSet
+from collections.abc import Mapping, MutableMapping, KeysView, ItemsView
+from collections.abc import Sequence, MutableSequence
+from collections.abc import ByteString
 
 TestNT = namedtuple('TestNT', 'x y z')    # type used for pickle tests
 
@@ -507,7 +508,7 @@ def test_issue_5647(self):
 
     def test_issue_4920(self):
         # MutableSet.pop() method did not work
-        class MySet(collections.MutableSet):
+        class MySet(MutableSet):
             __slots__=['__s']
             def __init__(self,items=None):
                 if items is None:
@@ -553,7 +554,7 @@ def test_Mapping(self):
             self.assertTrue(issubclass(sample, Mapping))
         self.validate_abstract_methods(Mapping, '__contains__', '__iter__', '__len__',
             '__getitem__')
-        class MyMapping(collections.Mapping):
+        class MyMapping(Mapping):
             def __len__(self):
                 return 0
             def __getitem__(self, i):