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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 host(self, host):
 """ Return the configuration of a specific host as a dictionary. Dictionary always contains lowercase versions of the attribute names. Parameters host : the host to return values for. Returns ------- dict of key value pairs, excluding "Host", empty map if host is not found. """

        if host in self.hosts_:
            vals = defaultdict(list)
            for k, value in [(x.key.lower(), x.value) for x in self.lines_
                             if x.host == host and x.key.lower() != "host"]:
                vals[k].append(value)
            flatten = lambda x: x[0] if len(x) == 1 else x
            return {k: flatten(v) for k, v in vals.items()}
        return {}