old_contents: from msmbuilder.example_datasets import MullerPotential, load_muller, load_doublewell
  
  
  def test_1():
      xx = load_muller(random_state=1)['trajectories']
      assert len(xx) == 10
      assert xx[0].ndim == 2
      assert xx[0].shape[1] == 2
  
      print(load_muller())
  
new_contents: from msmbuilder.example_datasets import load_muller, MullerPotential
  from msmbuilder.utils import array2d
  
  
  def test_func():
      xx = load_muller(random_state=1)['trajectories']
      assert len(xx) == 10
      assert xx[0].ndim == 2
      assert xx[0].shape[1] == 2
      array2d(xx)
  
  
  def test_class():
      xx = MullerPotential(random_state=123122).get()['trajectories']
      assert len(xx) == 10
      assert xx[0].ndim == 2
      assert xx[0].shape[1] == 2
      array2d(xx)
  
subject: Update test for muller