old_contents: """Test LinkedList class."""
  
  import pytest
  
  
  LIST_DATA = [
      ['string'],
      [123],
      [[]],
      [{}]
  ]
  
  
  @pytest.mark.parametrize("n", LIST_DATA)
  def test_initiate_linkedlist(n):
      """Test if attributes in linked list match what is expected."""
      from linked_list import Node
      example = Node(n)
      assert example.data == n
  
  
  @pytest.mark.parametrize("n", LIST_DATA)
  def test_push(n):
      """Test push updates head of the linked list."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push(n)
      assert linked_list.head.data == n
  
  
  def test_size():
      """Test if size returns the number of objects in list."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push('1')
      linked_list.push('2')
      linked_list.push('3')
      assert linked_list.size() == 3
  
  
  def test_pop():
      """Test pop method if removes the first value and return it."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push('1')
      linked_list.push('2')
      linked_list.push('3')
      popped_item = linked_list.pop()
      assert popped_item == '3'
  
new_contents: """Test LinkedList class."""
  
  import pytest
  
  
  LIST_DATA = [
      ['string'],
      [123],
      [[]],
      [{}]
  ]
  
  
  @pytest.mark.parametrize("n", LIST_DATA)
  def test_initiate_linkedlist(n):
      """Test if attributes in linked list match what is expected."""
      from linked_list import Node
      example = Node(n)
      assert example.data == n
  
  
  @pytest.mark.parametrize("n", LIST_DATA)
  def test_push(n):
      """Test push updates head of the linked list."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push(n)
      assert linked_list.head.data == n
  
  
  def test_size():
      """Test if size returns the number of objects in list."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push('1')
      linked_list.push('2')
      linked_list.push('3')
      assert linked_list.size() == 3
  
  
  def test_pop():
      """Test pop method if removes the first value and return it."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push('1')
      linked_list.push('2')
      linked_list.push('3')
      popped_item = linked_list.pop()
      assert popped_item == '3'
  
  
  def test_search():
      """Test search method if finds a value in linked_list."""
      from linked_list import LinkedList
      linked_list = LinkedList()
      linked_list.push('1')
      linked_list.push('2')
      linked_list.push('3')
      assert linked_list.search('2').data == '2'
  
subject: test if search method returns node