Function parse_ticker_to_mark_price 

pub fn parse_ticker_to_mark_price(
    msg: &DeribitTickerMsg,
    instrument: &InstrumentAny,
    ts_init: UnixNanos,
) -> Result<MarkPriceUpdate>

Parses a Deribit ticker message into a Nautilus MarkPriceUpdate.

Errors

Returns an error if the price cannot be converted to the required precision.