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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 lookup(self, hostname):
 """ Return a dict of config options for a given hostname. The host-matching rules of OpenSSH's C{ssh_config} man page are used, which means that all configuration options from matching host specifications are merged, with more specific hostmasks taking precedence. In other words, if C{"Port"} is set under C{"Host *"} and also C{"Host *.example.com"}, and the lookup is for C{"ssh.example.com"}, then the port entry for C{"Host *.example.com"} will win out. The keys in the returned dict are all normalized to lowercase (look for C{"port"}, not C{"Port"}. No other processing is done to the keys or values. @param hostname: the hostname to lookup @type hostname: str """

        matches = [x for x in self._config if fnmatch.fnmatch(hostname, x['host'])]
        # Move * to the end
        _star = matches.pop(0)
        matches.append(_star)
        ret = {}
        for m in matches:
            for k,v in m.iteritems():
                if not k in ret:
                    ret[k] = v
        ret = self._expand_variables(ret, hostname)
        del ret['host']
        return ret