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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 ping(self) -> None: """Pings a database connection, reconnecting if necessary."""

        if self.db is None or self.db_pythonlib not in [PYTHONLIB_MYSQLDB,
                                                        PYTHONLIB_PYMYSQL]:
            return
        try:
            self.db.ping(True)  # test connection; reconnect upon failure
            # ... should auto-reconnect; however, it seems to fail the first
            # time, then work the next time.
            # Exception (the first time) is:
            # <class '_mysql_exceptions.OperationalError'>:
            #   (2006, 'MySQL server has gone away')
            # http://mail.python.org/pipermail/python-list/2008-February/
            #        474598.html
        except mysql.OperationalError:  # loss of connection
            self.db = None
            self.connect_to_database_mysql(
                self._database, self._user, self._password, self._server,
                self._port, self._charset, self._use_unicode)