@webapi_check_local_site
    @webapi_login_required
    @webapi_response_errors(DOES_NOT_EXIST, NOT_LOGGED_IN, PERMISSION_DENIED)
    @webapi_request_fields(
        optional=BaseFileAttachmentCommentResource.OPTIONAL_UPDATE_FIELDS,
        allow_unknown=True
    )
    def update(self, request, *args, **kwargs):
        """Updates a file comment.

        This can update the text or region of an existing comment. It
        can only be done for comments that are part of a draft review.
        """
        try:
            resources.review_request.get_object(request, *args, **kwargs)
            review = resources.review.get_object(request, *args, **kwargs)
            file_comment = self.get_object(request, *args, **kwargs)
        except __HOLE__:
            return DOES_NOT_EXIST

        # Determine whether or not we're updating the issue status.
        if self.should_update_issue_status(file_comment, **kwargs):
            return self.update_issue_status(request, self, *args, **kwargs)

        if not resources.review.has_modify_permissions(request, review):
            return self.get_no_access_error(request)

        self.update_comment(file_comment, **kwargs)

        return 200, {
            self.item_result_key: file_comment,
        }
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/webapi/resources/review_file_attachment_comment.py/ReviewFileAttachmentCommentResource.update