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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_file_argument(self, *args, mode='r', buffering=1, filetype_options=None, **kwargs):
 """ Add a tab-completion safe FileType argument. This argument differs from a normal argparse.FileType based argument in that the value is a factory function that returns a file handle instead of providing an already open file handle. There are various reasons why this is a better approach but it is also required to avoid erroneous creation of files with shellish tab completion. """

        type_ = supplement.SafeFileType(mode=mode, bufsize=buffering,
                                        **filetype_options or {})
        return self.add_argument(*args, type=type_, **kwargs)