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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 dump(self):
 """Serialize the state of this stream walker. Returns: dict: The serialized state. """


        reading = self.reading
        if reading is not None:
            reading = reading.asdict()

        return {
            u'selector': str(self.selector),
            u'reading': reading
        }