import binascii


def hexlify(digest):
  """Get the hex-string representation of a digest.

  @param digest: A series of bytes comprising the digest.
  eg. A SHA-1 digest will be 20 bytes.
  @type digest: str/bytes

  @return: A string containing the hexadecimal string representation of the
  digest.
  @rtype: unicode
  """
  return binascii.hexlify(digest).decode("utf8")