new_contents: from __future__ import absolute_import, print_function, unicode_literals
  from builtins import dict, str
  from future.utils import python_2_unicode_compatible
  
  
  __all__ = ['make_hash']
  
  
  from hashlib import md5
  
  
  def make_hash(s, n_bytes):
      """Make the hash from a matches key."""
      raw_h = int(md5(s.encode('utf-8')).hexdigest()[:n_bytes], 16)
      # Make it a signed int.
      return 16**n_bytes//2 - raw_h
subject: Split off util functions