code: def _none_to_empty_2d(arg):
      if arg is None:
          return zeros((0, 0))
      else:
          return arg
  
file_path: catboost/contrib/python/scipy/py2/scipy/signal/lti_conversion.py
imports: from __future__ import division, print_function, absolute_import
  import numpy
  import numpy
  from numpy import r_, eye, atleast_2d, poly, dot, asarray, product, zeros, array, outer
  from scipy import linalg
  from .filter_design import tf2zpk, zpk2tf, normalize
label_desc: Use image node_id 2 for calling a global function with example usage: _none_to_empty_2d(arg) and returns: zeros, arg