関連ワード:  check if a value is in list python    check if a value is present in list python    check if a value is not in list python    check if a variable is list in python    check if string value is in list python    test if a value is in a list python    check for a value in list python    check if a value is already in a list python    check if value is duplicate in list python    check if value is unique in list python