diff --git a/easywebdav/client.py b/easywebdav/client.py
index 4003198..287b398 100644
--- a/easywebdav/client.py
+++ b/easywebdav/client.py
@@ -9,9 +9,11 @@
 if py_majversion == '2':
     from httplib import responses as HTTP_CODES
     from urlparse import urlparse
+    basestring = basestring
 else:
     from http.client import responses as HTTP_CODES
     from urllib.parse import urlparse
+    basestring = (str,bytes)
 
 DOWNLOAD_CHUNK_SIZE_BYTES = 1 * 1024 * 1024