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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def post_build(self, p, pay):
 """Called implicitly before a packet is sent. """

    p += pay
    if self.auxdlen != 0:
      print("NOTICE: A properly formatted and complaint V3 Group Record should have an Auxiliary Data length of zero (0).")
      print("        Subsequent Group Records are lost!")
    return p