関連ワード:  how to use nested for loop in python    how to use double for loop in python    how to use nested for loop in list comprehension python    how to use nested while loop in python    how to create a nested for loop in python    how to create nested list using for loop in python    how to use nested if statements in python    how to nested for loop in python    how to break nested for loop in python    how to optimize nested for loop in python