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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 set_pid_file(self, fpath, before_priv_drop=True, safe=False):
 """Creates pidfile before or after privileges drop. :param str|unicode fpath: File path. :param bool before_priv_drop: Whether to create pidfile before privileges are dropped. .. note:: Vacuum is made after privileges drop, so it may not be able to delete PID file if it was created before dropping. :param bool safe: The safe-pidfile works similar to pidfile but performs the write a little later in the loading process. This avoids overwriting the value when app loading fails, with the consequent loss of a valid PID number. """

        command = 'pidfile'

        if not before_priv_drop:
            command += '2'

        if safe:
            command = 'safe-' + command

        self._set(command, fpath)

        return self._section