code: def nice_identifier():
      'do not use uuid.uuid4, because it can block'
      big = reduce(mul, struct.unpack('<LLLL', os.urandom(16)), 1)
      big = big % 2**128
      return uuid.UUID(int=big).hef nice_identifier():
      'do not use uuid.uuid4, because it can block'
      big = reduce(mul, struct.unpack('<LLLL', os.urandom(16)), 1)
      big = big % 2**128
      return uuid.UUID(int=big).hex
docs: do not use uuid.uuid4, because it can block