def METHOD_NAME(self):
    coord_one = Mock(__class__=AuxCoord, long_name="one")
    coord_two = Mock(__class__=AuxCoord, long_name="two")
    input_list = [coord_one, coord_two]
    result = metadata_filter(input_list, item=coord_one, long_name="one")
    self.assertIn(coord_one, result)
    self.assertNotIn(coord_two, result)