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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 _add_command(parser, subparser_fn, handler, cell_required=False, cell_prohibited=False):
 """ Create and initialize a pipeline subcommand handler. """

  sub_parser = subparser_fn(parser)
  sub_parser.set_defaults(func=lambda args, cell: _dispatch_handler(
      args, cell, sub_parser, handler, cell_required=cell_required,
      cell_prohibited=cell_prohibited))