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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 comments(self, update=True):
 """Fetch and return the comments for a single MoreComments object."""

        if not self._comments:
            if self.count == 0:  # Handle 'continue this thread' type
                return self._continue_comments(update)
            # pylint: disable=W0212
            children = [x for x in self.children if 't1_{0}'.format(x)
                        not in self.submission._comments_by_id]
            # pylint: enable=W0212
            if not children:
                return None
            data = {'children': ','.join(children),
                    'link_id': self.submission.fullname,
                    'r': str(self.submission.subreddit)}

            # pylint: disable=W0212
            if self.submission._comment_sort:
                data['where'] = self.submission._comment_sort
            # pylint: enable=W0212
            url = self.reddit_session.config['morechildren']
            response = self.reddit_session.request_json(url, data=data)
            self._comments = response['data']['things']
            if update:
                for comment in self._comments:
                    # pylint: disable=W0212
                    comment._update_submission(self.submission)
                    # pylint: enable=W0212
        return self._comments