関連ワード:  what is use of self in python    what is the use of self in python class    what is use of self keyword in python    what is the use of self in python functions    what is the use of self in python with example    what is the use of self parameter in python    what is the use of self function in python    what is the use of self argument in python    what is self in python with example    what is self. in python