def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def remove_attributes(self, model):
        """
        Removes the x and y attributes which were added by the forward handles
        Recursively searches for non-container layers
        """
        for child in model.children():
            if 'nn.modules.container' in str(type(child)):
                self.remove_attributes(child)
            else:
                try:
                    del child.x
                except AttributeError:
                    pass
                try:
                    del child.y
                except AttributeError:
                    pass