code: def to_cv_sigma(sigma, axes=2):
      if sigma is None:
          return (0,) * axes
      elif isinstance(sigma, (int, float)):
          return (sigma,) * axes
      elif isinstance(sigma, np.ndarray) and len(sigma.shape) == 0:
          return (float(sigma),) * axes
      elif len(sigma) == 1:
          return (sigma[0],) * axes
      return tuple(reversed(sigma))
  
imports: from nvidia.dali.pipeline import Pipeline, pipeline_def
  import nvidia.dali.types
  import nvidia.dali.fn
  import numpy
  import cv2
  from scipy.ndimage import convolve1d
  import os
  from nose_utils import assert_raises, raises
  from nose.plugins.attrib import attr
  from sequences_test_utils import video_suite_helper, ArgCb
  from test_utils import get_dali_extra_path, check_batch, compare_pipelines, RandomlyShapedDataIterator, dali_type
label_desc: Use image node_id 2 for calling a global function with example usage: to_cv_sigma(sigma, axes) and returns: tuple, unknown, unknown, unknown, unknown