関連ワード:  how to define linked list in python    how to create linked list in python    how to declare linked list in python    how to create singly linked list in python    how to create empty linked list in python    how to create doubly linked list in python    how to create new linked list in python    how to create a circular linked list in python    how to set up a linked list in python    how to create a node in linked list in python