liniting fixes

Author: jdugan1024

graphene/core/types/custom_scalars.py

@@ -1,4 +1,3 @@
-import datetime
 import json
 import iso8601
 

graphene/core/types/tests/test_custom_scalars.py

@@ -4,9 +4,11 @@
 
 from ..custom_scalars import DateTime
 
+
 def test_date_time():
     test_iso_string = "2016-04-29T18:34:12.502Z"
 
+
     def check_datetime(test_dt):
         assert test_dt.tzinfo == iso8601.UTC
         assert test_dt.year == 2016
@@ -24,4 +26,3 @@ def check_datetime(test_dt):
     node = StringValue(test_iso_string)
     test_dt = DateTime.parse_literal(node)
     check_datetime(test_dt)
-