How to use the javaproperties.util.LinkedList function in javaproperties

def test_linked_list_insert_after_last():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    nx = n3.insert_after(3.14)
    assert list(ll) == [42, 'fnord', [0, 1, 2], 3.14]
    assert list(ll.iternodes()) == [n1, n2, n3, nx]
    assert ll.find_node(n1) == 0
    assert ll.find_node(n2) == 1
    assert ll.find_node(n3) == 2
    assert ll.find_node(nx) == 3
    assert ll.start is n1
    assert ll.end is nx
    assert n1.prev is None
    assert n1.next is n2
    assert n2.prev is n1
    assert n2.next is n3

def test_linkedlist_empty():
    ll = LinkedList()
    assert list(ll) == []
    assert list(ll.iternodes()) == []
    assert ll.start is None
    assert ll.end is None

def test_linked_list_insert_before_middle():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    nx = n2.insert_before(3.14)
    assert list(ll) == [42, 3.14, 'fnord', [0, 1, 2]]
    assert list(ll.iternodes()) == [n1, nx, n2, n3]
    assert ll.find_node(n1) == 0
    assert ll.find_node(n2) == 2
    assert ll.find_node(n3) == 3
    assert ll.find_node(nx) == 1
    assert ll.start is n1
    assert ll.end is n3
    assert n1.prev is None
    assert n1.next is nx
    assert nx.prev is n1
    assert nx.next is n2

def test_linked_list_insert_before_first():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    nx = n1.insert_before(3.14)
    assert list(ll) == [3.14, 42, 'fnord', [0, 1, 2]]
    assert list(ll.iternodes()) == [nx, n1, n2, n3]
    assert ll.find_node(n1) == 1
    assert ll.find_node(n2) == 2
    assert ll.find_node(n3) == 3
    assert ll.find_node(nx) == 0
    assert ll.start is nx
    assert ll.end is n3
    assert nx.prev is None
    assert nx.next is n1
    assert n1.prev is nx
    assert n1.next is n2

def test_linked_list_unlink_only():
    ll = LinkedList()
    n = ll.append(42)
    n.unlink()
    assert list(ll) == []
    assert list(ll.iternodes()) == []
    assert ll.start is None
    assert ll.end is None
    assert ll.find_node(n) is None

def test_linked_list_insert_after_first():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    nx = n1.insert_after(3.14)
    assert list(ll) == [42, 3.14, 'fnord', [0, 1, 2]]
    assert list(ll.iternodes()) == [n1, nx, n2, n3]
    assert ll.find_node(n1) == 0
    assert ll.find_node(n2) == 2
    assert ll.find_node(n3) == 3
    assert ll.find_node(nx) == 1
    assert ll.start is n1
    assert ll.end is n3
    assert n1.prev is None
    assert n1.next is nx
    assert nx.prev is n1
    assert nx.next is n2

def test_linked_list_unlink_middle():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    n2.unlink()
    assert list(ll) == [42, [0, 1, 2]]
    assert list(ll.iternodes()) == [n1, n3]
    assert ll.find_node(n1) == 0
    assert ll.find_node(n2) is None
    assert ll.find_node(n3) == 1
    assert ll.start is n1
    assert ll.end is n3
    assert n1.prev is None
    assert n1.next is n3
    assert n3.prev is n1
    assert n3.next is None

def test_linked_list_unlink_first():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    n3 = ll.append([0, 1, 2])
    n1.unlink()
    assert list(ll) == ['fnord', [0, 1, 2]]
    assert list(ll.iternodes()) == [n2, n3]
    assert ll.find_node(n1) is None
    assert ll.find_node(n2) == 0
    assert ll.find_node(n3) == 1
    assert ll.start is n2
    assert ll.end is n3
    assert n2.prev is None
    assert n2.next is n3
    assert n3.prev is n2
    assert n3.next is None

def test_linkedlist_two_elem():
    ll = LinkedList()
    n1 = ll.append(42)
    n2 = ll.append('fnord')
    assert list(ll) == [42, 'fnord']
    assert list(ll.iternodes()) == [n1, n2]
    assert ll.find_node(n1) == 0
    assert ll.find_node(n2) == 1
    assert ll.start is n1
    assert ll.end is n2
    assert n1.prev is None
    assert n1.next is n2
    assert n2.prev is n1
    assert n2.next is None

def test_linkedlist_one_elem():
    ll = LinkedList()
    n = ll.append(42)
    assert list(ll) == [42]
    assert list(ll.iternodes()) == [n]
    assert ll.find_node(n) == 0
    assert ll.start is n
    assert ll.end is n
    assert n.prev is None
    assert n.next is None