Remove mutable default arguments.

lib/ansible/module_utils/cloudstack.py

@@ -150,7 +150,9 @@ class AnsibleCloudStack(object):
         return False
 
 
-    def _get_by_key(self, key=None, my_dict={}):
+    def _get_by_key(self, key=None, my_dict=None):
+        if my_dict is None:
+            my_dict = {}
         if key:
             if key in my_dict:
                 return my_dict[key]

lib/ansible/module_utils/urls.py

@@ -400,7 +400,9 @@ class RequestWithMethod(urllib2.Request):
     Originally contained in library/net_infrastructure/dnsmadeeasy
     '''
 
-    def __init__(self, url, method, data=None, headers={}):
+    def __init__(self, url, method, data=None, headers=None):
+        if headers is None:
+            headers = {}
         self._method = method
         urllib2.Request.__init__(self, url, data, headers)