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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 on_change(self, path, event_type):
 """Respond to changes in the file system This method will be given the path to a file that has changed on disk. We need to reload the keywords from that file """

        # I can do all this work in a sql statement, but
        # for debugging it's easier to do it in stages.
        sql = """SELECT collection_id
                 FROM collection_table
                 WHERE path == ?
        """
        cursor = self._execute(sql, (path,))
        results = cursor.fetchall()
        # there should always be exactly one result, but
        # there's no harm in using a loop to process the
        # single result
        for result in results:
            collection_id = result[0]
            # remove all keywords in this collection
            sql = """DELETE from keyword_table
                     WHERE collection_id == ?
            """
            cursor = self._execute(sql, (collection_id,))
            self._load_keywords(collection_id, path=path)