old_contents: """Test `demo.py` files in model dirs."""
  
  from importlib import import_module
  
  import pytest
  from matplotlib import pyplot as plt
  
  import dapper as dpr
  
  plt.ion()
  
  
  @pytest.mark.parametrize(("path"), dpr._find_demos())
  def test_imp(path):
      import_module(path)
      assert True
  
new_contents: """Test `demo.py` files in model dirs."""
  
  from importlib import import_module
  
  import matplotlib as mpl
  import pytest
  from matplotlib import pyplot as plt
  
  import dapper as dpr
  
  mpl.use("Qt5Agg")
  plt.ion()
  
  
  @pytest.mark.parametrize(("path"), dpr._find_demos())
  def test_imp(path):
      import_module(path)
      assert True
  
subject: Fix test_demos on ubuntu