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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 handle_user(self, params):
 """ Handle the USER command which identifies the user to the server. """

        params = params.split(' ', 3)

        if len(params) != 4:
            raise IRCError.from_name(
                'needmoreparams',
                'USER :Not enough parameters')

        user, mode, unused, realname = params
        self.user = user
        self.mode = mode
        self.realname = realname
        return ''