code: def show_both_bundles(bundles, colors=None, show=True, fname=None):
      scene = window.Scene()
      scene.SetBackground(1.0, 1, 1)
      for i, bundle in enumerate(bundles):
          color = colors[i]
          streamtube_actor = actor.streamtube(
              bundle, color, linewidth=0.3
          )
          streamtube_actor.RotateX(-90)
          streamtube_actor.RotateZ(90)
          scene.add(streamtube_actor)
      if show:
          window.show(scene)
      if fname is not None:
          window.record(
              scene, n_frames=1, out_path=fname, size=(900, 900)
          )
  
imports: import numpy
  from dipy.viz import window, actor
  from dipy.segment.bundles import bundle_shape_similarity
  from dipy.segment.bundles import select_random_set_of_streamlines
  from dipy.data import two_cingulum_bundles
label_desc: Use image node_id 1 for calling a global function with example usage: show_both_bundles(bundles, colors, show, fname) without return types