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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 wait(self, timeout=None):
 """Wait for a change in the journal. `timeout` is the maximum time in seconds to wait, or None which means to wait forever. Returns one of NOP (no change), APPEND (new entries have been added to the end of the journal), or INVALIDATE (journal files have been added or removed). """

        us = -1 if timeout is None else int(timeout * 1000000)
        return super(Reader, self).wait(us)