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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 rewind(self, places):
        '''Rewinds the current buffer to a position. Needed for reading varints,
        because we might read bytes that belong to the stream after the varint.
        '''
        log.debug("Rewinding pos %d with %d places" % (self.pos, places))
        self.pos -= places
        log.debug("Reset buffer to pos %d" % self.pos)