def _to_extended_delta_code(seconds: int) -> str:
    """Return the deltaCode encoding for the ExtendedZoneProcessor which is
    roughly: deltaCode = (deltaSeconds + 1h) / 15m. Using the lower 4-bits of
    the uint8_t field, this will handle deltaOffsets from -1:00 to +2:45.
    """
    return f"({seconds // 900} + 4)"