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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 start(self):
 """ Start the HTTP change monitoring thread. """

        # Store reference to message queue in module global variable, so that
        # our Bottle app handler functions have easy access to it.
        global _Q_ROUTE_SPEC
        _Q_ROUTE_SPEC = self.q_route_spec

        logging.info("Http watcher plugin: "
                     "Starting to watch for route spec on "
                     "'%s:%s/route_spec'..." %
                     (self.conf['addr'], self.conf['port']))