関連ワード:  add a column in a dataframe python    insert a column in a dataframe python    add a new column in a dataframe python    add a column in a dataframe pandas    add a column in a pandas dataframe based on an if else    creating a new column in a dataframe python    add a calculated column in dataframe python    add a empty column in dataframe python    append a column to a dataframe python    add a column to a dataframe in python with the same value