new_contents: import os
  import tempfile
  
  import pytest
  from numpy import cos, exp
  
  from cxroots import Circle
  
  
  @pytest.fixture()
  def results_dir():
      with tempfile.TemporaryDirectory() as tmp:
          yield tmp
  
  
  def test_save_plot(results_dir):
      file_path = os.path.join(results_dir, "circle.pdf")
      Circle(1j, 2).show(save_file=file_path)
      assert os.path.exists(file_path)
  
  
  def test_save_animation(results_dir):
      file_path = os.path.join(results_dir, "circle.gif")
      Circle(1j, 2).demo_roots(f=lambda z: cos(exp(1j * z)), save_file=file_path)
      assert os.path.exists(file_path)
  
  
  def test_save_roots(results_dir):
      file_path = os.path.join(results_dir, "roots.png")
      Circle(1j, 2).roots(f=lambda z: cos(exp(1j * z))).show(save_file=file_path)
      assert os.path.exists(file_path)
  
subject: Create test_plotting.py (#214)