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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 add(self, host, **kwargs):
 """ Add another host to the SSH configuration. Parameters host: The Host entry to add. **kwargs: The parameters for the host (without "Host" parameter itself) """

        if host in self.hosts_:
            raise ValueError("Host %s: exists (use update)." % host)
        self.hosts_.add(host)
        self.lines_.append(ConfigLine(line="", host=None))
        self.lines_.append(ConfigLine(line="Host %s" % host, host=host, key="Host", value=host))
        for k, v in kwargs.items():
            if type(v) not in [list, tuple]:
                v = [v]
            mapped_k = _remap_key(k)
            for value in v:
                self.lines_.append(ConfigLine(line="  %s %s" % (mapped_k, str(value)), host=host, key=mapped_k, value=value))
        self.lines_.append(ConfigLine(line="", host=None))