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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 _GenClientLibCallback(args, client_func=_GenClientLib):
 """Generate a client library to file. 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 path to a discovery doc, a client library language, an output directory, and a build system for the client library language. """

  client_path = client_func(args.discovery_doc[0], args.language, args.output,
                            args.build_system)
  print 'API client library written to %s' % client_path