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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 matches(self, query):
 """ Check if this thread matches the given notmuch query. :param query: The query to check against :type query: string :returns: True if this thread matches the given query, False otherwise :rtype: bool """

        thread_query = 'thread:{tid} AND {subquery}'.format(tid=self._id,
                                                            subquery=query)
        num_matches = self._dbman.count_messages(thread_query)
        return num_matches > 0