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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 get_so_far(self):
 """ Returns the `str` bytes of this message that have been parsed and returned. The string passed into a message's constructor can be regenerated by concatenating ``get_so_far`` and `get_remainder`. """

        position = self.packet.tell()
        self.rewind()
        return self.packet.read(position)