code: def bearing_bundles(nb_balls=6, bearing_radius=2):
      bundles = []
  
      for theta in np.linspace(0, 2 * np.pi, nb_balls, endpoint=False):
          x = bearing_radius * np.cos(theta)
          y = bearing_radius * np.sin(theta)
  
          bundle = np.array(straight_bundle(nb_streamlines=100))
          bundle += (x, y, 0)
          bundles.append(bundle)
  
      return bundles
  
imports: import itertools
  import numpy
  from numpy.testing import assert_array_equal, assert_equal, assert_raises
  from dipy.segment.clustering import QuickBundlesX, QuickBundles, qbx_and_merge
  from dipy.segment.featurespeed import ResampleFeature
  from dipy.segment.metricspeed import AveragePointwiseEuclideanMetric, MinimumAverageDirectFlipMetric
  from dipy.tracking.streamline import set_number_of_points
  from dipy.tracking.streamline import Streamlines
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 2 for calling a global function with example usage: bearing_bundles(nb_balls, bearing_radius) and returns: bundles