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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 to_json(self, filename=None, encoding="utf-8", errors="strict", multiline=False, **json_kwargs):
 """ Transform the BoxList object into a JSON string. :param filename: If provided will save to file :param encoding: File encoding :param errors: How to handle encoding errors :param multiline: Put each item in list onto it's own line :param json_kwargs: additional arguments to pass to json.dump(s) :return: string of JSON or return of `json.dump` """

        if filename and multiline:
            lines = [_to_json(item, filename=False, encoding=encoding,
                              errors=errors, **json_kwargs) for item in self]
            with open(filename, 'w', encoding=encoding, errors=errors) as f:
                f.write("\n".join(lines).decode('utf-8') if
                        sys.version_info < (3, 0) else "\n".join(lines))
        else:
            return _to_json(self.to_list(), filename=filename,
                            encoding=encoding, errors=errors, **json_kwargs)