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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 _GetClientLib(service_class_names, language, output_path, build_system, hostname=None, application_path=None):
 """Fetch client libraries from a cloud service. Args: service_class_names: A list of fully qualified ProtoRPC service names. language: The client library language to generate. (java) output_path: The directory to output the discovery docs to. build_system: The target build system for the client library language. hostname: A string hostname which will be used as the default version hostname. If no hostname is specificied in the @endpoints.api decorator, this value is the fallback. Defaults to None. application_path: A string containing the path to the AppEngine app. Returns: A list of paths to client libraries. """

  client_libs = []
  service_configs = GenApiConfig(
      service_class_names, hostname=hostname,
      config_string_generator=discovery_generator.DiscoveryGenerator(),
      application_path=application_path)
  for api_name_version, config in service_configs.iteritems():
    client_name = api_name_version + '.zip'
    client_libs.append(
        _GenClientLibFromContents(config, language, output_path,
                                  build_system, client_name))
  return client_libs