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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 _GetClientLibCallback(args, client_func=_GetClientLib):
 """Generate discovery docs and client libraries to files. Args: args: An argparse.Namespace object to extract parameters from. client_func: A function that generates client libraries and stores them to files, accepting a list of service names, a client library language, an output directory, a build system for the client library language, and a hostname. """

  client_paths = client_func(
      args.service, args.language, args.output, args.build_system,
      hostname=args.hostname, application_path=args.application)

  for client_path in client_paths:
    print 'API client library written to %s' % client_path