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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 _reconnect(self):
 """Closes the existing database connection and re-opens it."""

        self.close()
        self._db = psycopg2.connect(**self._db_args)

        if self._search_path:
            self.execute('set search_path=%s;' % self._search_path)

        if self._timezone:
            self.execute("set timezone='%s';" % self._timezone)