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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 dump_by_server(self, hosts):
 """Returns the output of dump for each server. :param hosts: comma separated lists of members of the ZK ensemble. :returns: A dictionary of ((server_ip, port), ClientInfo). """

        dump_by_endpoint = {}

        for endpoint in self._to_endpoints(hosts):
            try:
                out = self.cmd([endpoint], "dump")
            except self.CmdFailed as ex:
                out = ""
            dump_by_endpoint[endpoint] = out

        return dump_by_endpoint