def METHOD_NAME(self):
    """Tests that get_xyz_dict correctly filters for free tile layers."""
    xyz_dict_free = get_xyz_dict(free_only=True)
    xyz_dict_all = get_xyz_dict(free_only=False)
    self.assertNotIn("b", xyz_dict_free.keys())
    self.assertIn("b", xyz_dict_all.keys())