Remove types module it is not compatible in python 3x

Author: rajumsys

sparkpost/transmissions.py

@@ -2,7 +2,6 @@
 import copy
 import json
 from email.utils import parseaddr
-import types
 
 from .base import Resource
 from .exceptions import SparkPostException
@@ -140,10 +139,7 @@ def _parse_address(self, address):
 
     def _extract_recipients(self, recipients):
 
-        if not (
-            isinstance(recipients, types.ListType) or
-            isinstance(recipients, types.DictType)
-        ):
+        if not (isinstance(recipients, list) or isinstance(recipients, dict)):
             raise SparkPostException('recipients must be a list or dict')
 
         formatted_recipients = []