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 encode(value):
    if isinstance(value, bytes):
        value = value.decode(errors="surrogateescape")

    for char in ("\\", "\n", "\t"):
        value = value.replace(
            char, char.encode(encoding="unicode-escape").decode()
        )

    return value