code: def is_control(char):
      """Checks whether `chars` is a control character.
      These are technically control characters but we count them as whitespace characters.
      """
      if char == "\t" or char == "\n" or char == "\r":
          return False
      cat = unicodedata.category(char)
      if cat.startswith("C"):
          return True
      return False
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import unicodedata
  import six
label_desc: Use image node_id 2 for calling a global function with example usage: is_control(char) and returns: False, False, True