関連ワード:  how to create nested loops in python    how to use nested loops in python    how to use nested while loop in python    how to create a nested while loop in python    how to create nested list using for loop in python    how to use multiple while loops in python    how to use multiple for loops in python    how to use nested if statement in python    how to create multiple dataframes in a loop in python    how to create multiple variables in for loop python