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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 main(self):
 """Main beautifying function."""

        error = False
        parser = argparse.ArgumentParser(
            description="A Bash beautifier for the masses, version {}".format(self.get_version()), add_help=False)
        parser.add_argument('--indent-size', '-i', nargs=1, type=int, default=4,
                            help="Sets the number of spaces to be used in "
                                 "indentation.")
        parser.add_argument('--files', '-f', nargs='*',
                            help="Files to be beautified. This is mandatory. "
                            "If - is provided as filename, then beautysh reads "
                            "from stdin and writes on stdout.")
        parser.add_argument('--backup', '-b', action='store_true',
                            help="Beautysh will create a backup file in the "
                                 "same path as the original.")
        parser.add_argument('--check', '-c', action='store_true',
                            help="Beautysh will just check the files without doing "
                                 "any in-place beautify.")
        parser.add_argument('--tab', '-t', action='store_true',
                            help="Sets indentation to tabs instead of spaces.")
        parser.add_argument('--force-function-style', '-s', nargs=1,
                            help="Force a specific Bash function formatting. See below for more info.")
        parser.add_argument('--version', '-v', action='store_true',
                            help="Prints the version and exits.")
        parser.add_argument('--help', '-h', action='store_true',
                            help="Print this help message.")
        args = parser.parse_args()
        if (len(sys.argv) < 2) or args.help:
            self.print_help(parser)
            exit()
        if args.version:
            sys.stdout.write("%s\n" % self.get_version())
            exit()
        if(type(args.indent_size) is list):
            args.indent_size = args.indent_size[0]
        if not args.files:
            sys.stdout.write("Please provide at least one input file\n")
            exit()
        self.tab_size = args.indent_size
        self.backup = args.backup
        self.check_only = args.check
        if (args.tab):
            self.tab_size = 1
            self.tab_str = '\t'
        if (type(args.force_function_style) is list):
            provided_style = self.parse_function_style(args.force_function_style[0])
            if provided_style is None:
                sys.stdout.write("Invalid value for the function style. See --help for details.\n")
                exit()
            self.apply_function_style = provided_style
        for path in args.files:
            error |= self.beautify_file(path)
        sys.exit((0, 1)[error])