Merge branch '2.1'

1 files changed, 1 insertions, 6 deletions

diff --git a/paramiko/hostkeys.py b/paramiko/hostkeys.py
index 3e27fd52..d023b33d 100644
--- a/paramiko/hostkeys.py
+++ b/paramiko/hostkeys.py
@@ -20,17 +20,12 @@
 import binascii
 import os
 
+from collections import MutableMapping
 from hashlib import sha1
 from hmac import HMAC
 
 from paramiko.py3compat import b, u, encodebytes, decodebytes
 
-try:
-    from collections import MutableMapping
-except ImportError:
-    # noinspection PyUnresolvedReferences
-    from UserDict import DictMixin as MutableMapping
-
 from paramiko.dsskey import DSSKey
 from paramiko.rsakey import RSAKey
 from paramiko.util import get_logger, constant_time_bytes_eq