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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 upload(self, *args, **kwargs):
 """Convenience method for attaching files to a fetched record :param args: args to pass along to `Attachment.upload` :param kwargs: kwargs to pass along to `Attachment.upload` :return: upload response object """


        return self._resource.attachments.upload(self['sys_id'], *args, **kwargs)