'Test for inserting all column types as empty into a UserType as None\'s
test_can_insert_udts_with_nones tests that each cqlengine column type can be inserted into a UserType as None\'s.
It first creates a UserType that has each cqlengine column type, and a corresponding table/Model. It then creates
a UserType instance where all the fields are None\'s and inserts the UserType as an instance of the Model. Finally,
it verifies that each column read from the UserType from Cassandra is None.
@since 2.5.0
@jira_ticket PYTHON-251
@expected_result The UserType is inserted with each column type, and the resulting read yields None\'s for each column.
@test_category data_types:udt'

def test_can_insert_udts_with_nones(self):

    sync_table(AllDatatypesModel)
    self.addCleanup(drop_table, AllDatatypesModel)
    input = AllDatatypes(a=None, b=None, c=None, d=None, e=None, f=None, g=None, h=None, i=None, j=None, k=None, l=None, m=None, n=None)
    AllDatatypesModel.create(id=0, data=input)
    self.assertEqual(1, AllDatatypesModel.objects.count())
    output = AllDatatypesModel.objects.first().data
    self.assertEqual(input, output)
