new_contents: import pytest
  from insertion import insertion
  
  
  def test_merge():
      input = [54, 26, 93, 17, 71, 31, 44, 55, 20]
      assert insertion(input)[0] == [17, 20, 26, 31, 44, 54, 55, 71, 93]
  
  
  def test_merge():
      input = range(10000)
      assert insertion(input)[0] == range(10000)
  
  
  def test_merge_big_floats():
      input = [x*0.01 for x in range(0, 100)]
      assert insertion(input)[0] == [x*0.01 for x in range(0, 100)]
  
  
  def test_wrong_type():
      input = 'x'
      with pytest.raises(TypeError):
          insertion(input)[0]
  
  
  def test_wrong_type_in_list():
      input = [1, 2, 'a']
      with pytest.raises(TypeError):
          insertion(input)[0]
  
  
  def test_merge_big_reverse():
      input = range(10000)[::-1]
      assert insertion(input)[0] == range(10000)
  
  
  def test_merge_big_increase_decrease():
      input = range(5000)+range(5000)[::-1]
      expected = range(5000)*2
      expected.sort()
      assert insertion(input)[0] == expected
  
  
  def test_merge_duplicates():
      input = (range(100)+range(100))[::-1]
      expected = range(100)+range(100)
      expected.sort()
      assert insertion(input)[0] == expected
  
  
  def test_merge_all_duplicates():
      input = [100]*20
      assert insertion(input)[0] == [100]*20
  
subject: copy insertion tests