def get_column_pairs(self):
    return [(col1, col2) for (col1, col2) in itertools.product(self.categorical_columns, repeat=2) if (col1 != col2)]
def get_column_pairs(self):
    return [(col1, col2) for (col1, col2) in itertools.product(self.categorical_columns, repeat=2) if (col1 != col2)]