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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 mode(self, target, mode_string=None, tags=None):
 """Sends new modes to or requests existing modes from the given target."""

        params = [target]
        if mode_string:
            params += mode_string
        self.send('MODE', params=params, source=self.nick, tags=tags)