<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def format_string(self, s, args, kwargs):
 """If a format call is detected, then this is routed through this method so that our safety sandbox can be used for it. """

        if isinstance(s, Markup):
            formatter = SandboxedEscapeFormatter(self, s.escape)
        else:
            formatter = SandboxedFormatter(self)
        kwargs = _MagicFormatMapping(args, kwargs)
        rv = formatter.vformat(s, args, kwargs)
        return type(s)(rv)