@utilities.arguments_not_none<EOL><INDENT>def get_comment_form_for_update(self, comment_id):<DEDENT>
<EOL>collection = JSONClientValidated('<STR_LIT>',<EOL>collection='<STR_LIT>',<EOL>runtime=self._runtime)<EOL>if not isinstance(comment_id, ABCId):<EOL><INDENT>raise errors.InvalidArgument('<STR_LIT>')<EOL><DEDENT>if (comment_id.get_identifier_namespace() != '<STR_LIT>' or<EOL>comment_id.get_authority() != self._authority):<EOL><INDENT>raise errors.InvalidArgument()<EOL><DEDENT>result = collection.find_one({'<STR_LIT>': ObjectId(comment_id.get_identifier())})<EOL>obj_form = objects.CommentForm(osid_object_map=result, runtime=self._runtime, proxy=self._proxy)<EOL>self._forms[obj_form.get_id().get_identifier()] = not UPDATED<EOL>return obj_form<EOL>
Gets the comment form for updating an existing comment.

        A new comment form should be requested for each update
        transaction.

        arg:    comment_id (osid.id.Id): the ``Id`` of the ``Comment``
        return: (osid.commenting.CommentForm) - the comment form
        raise:  NotFound - ``comment_id`` is not found
        raise:  NullArgument - ``comment_id`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*