diff --git a/pkg_resources.py b/pkg_resources.py
index <HASH>..<HASH> 100644
--- a/pkg_resources.py
+++ b/pkg_resources.py
@@ -44,10 +44,6 @@ except ImportError:
     from urllib.parse import urlparse, urlunparse
 
 try:
-    frozenset
-except NameError:
-    from sets import ImmutableSet as frozenset
-try:
     basestring
     next = lambda o: o.next()
     from cStringIO import StringIO as BytesIO
Remove conditional import for frozenset (available in Python <I>+)