code: def _MakeList(input):
      """input is a tuple.
      Example:
      (a, b, c)   --> [a, b, c]
      (a)         --> [a]
      ([a, b, c]) --> [a, b, c]
      """
      if len(input) == 0:
          raise ValueError("input cannot be empty.")
      elif len(input) == 1:
          output = input[0]
          if not isinstance(output, list):
              output = [output]
      else:
          output = list(input)
      return output
  
imports: from caffe2.python import core
label_desc: Use image node_id 2 for calling a global function with example usage: _MakeList(input) and returns: output