code: def test_initialize(X):
      d = [Categorical(), ConditionalCategorical()]
      model = MarkovChain(d)
      assert model.d is None
      assert model.k == 1
      assert model._initialized == False
  
      model._initialize(2)
      assert model._initialized == True
      assert model.d == 2
      assert model.k == 1
  
imports: import numpy
  import torch
  import pytest
  from pomegranate.markov_chain import MarkovChain
  from pomegranate.distributions import Categorical
  from pomegranate.distributions import ConditionalCategorical
  from .distributions._utils import _test_initialization_raises_one_parameter
  from .distributions._utils import _test_initialization
  from .distributions._utils import _test_predictions
  from .distributions._utils import _test_efd_from_summaries
  from .distributions._utils import _test_raises
  from nose.tools import assert_raises
  from numpy.testing import assert_array_almost_equal
label_desc: Use image node_id 5 for calling a global function with example usage: test_initialize(X) without return types