If you want to actually concatenate them you have to use the dict.update() method.
tup = (x.update(y))This will create a single tuple(dict()):
tup = ({'field1': 'test1', 'field2': 'test2', 'field3': 'test3','field4': 'test4', 'field5': 'test5', 'field6': 'test6'})as opposed to:
tup = ({'field1': 'test1', 'field2': 'test2', 'field3': 'test3'}, y = {'field4': 'test4', 'field5': 'test5', 'field6': 'test6'})which is just adding the two dictionaries to a tuple.