code: def is_merge():
      parent2 = os.environ.get("HG_PARENT2", None)
      return parent2 is not None and len(parent2) > 0
  
imports: from __future__ import absolute_import, print_function, division
  import difflib
  import operator
  import os
  import string
  from subprocess import Popen, PIPE
  import sys
  import tabnanny
  import tokenize
  import reindent
  from six import StringIO
label_desc: Use image node_id 4 for calling a global function with example usage: is_merge() and returns: unknown