Check if part exists before trying to delete it (#659)

Author: mvantellingen

CHANGES

@@ -12,6 +12,7 @@ changes to the API.
  - Strip spaces from QName's when parsing xsd's (#719)
  - Fix DateTime parsing when only a date is returned (#672)
  - Fix handling of nested optional any elements (#556)
+ - Check if part exists before trying to delete it (#659)
 
 
 2.5.0 (2018-01-06)

src/zeep/wsdl/messages/soap.py

@@ -364,7 +364,7 @@ def _resolve_header(self, info, definitions, parts):
             part_name = item['part']
 
             message = definitions.get('messages', message_name)
-            if message == self.abstract:
+            if message == self.abstract and part_name in parts:
                 del parts[part_name]
 
             part = message.parts[part_name]