Pass in Attributes to the onBarUpdate() Callback Function Possible?

Is it possible to pass in features/variables to the onBarUpdate callback? I’m wanting to pass in the contract object to it so I can parse the contract’s symbol from it. What I have so far looks like this:

contracts = [Forex(pair) for pair in ('EURUSD', 'USDJPY', 'GBPUSD', 'USDCHF', 'USDCAD')]
ib.qualifyContracts(*contracts)

def onBarUpdate(bars, hasNewBar):
            
        df = util.df(bars)
        df.to_csv("datasets/" + todays_date + "/" + TICKER/CONTRACT_HERE + ".csv", index=True)


for contract in contracts:
    bars = ib.reqHistoricalData(contract, endDateTime='', durationStr='3 D', barSizeSetting='5 mins', whatToShow='MIDPOINT', useRTH=False, keepUpToDate=True)
    bars.updateEvent += onBarUpdate

…and what I envision I’m after would look something like:

def onBarUpdate(bars, hasNewBar, contract):
....
bars.updateEvent += onBarUpdate(contract)

…however I’m having issues troubleshooting this to get it working. As I’m sure can be guessed, I’d like to replace the “TICKER/CONTRACT_HERE” with something like “contract.symbol” so I could save the .csv file with the ticker for the corresponding bars contract in the filename. I’m just getting used to async callback functions as well so not sure the correct syntax. Any help would be greatly appreciated! Thanks!

[erdewit]

It’s easier to use bars.contract

[rundef]

You can use partial from functools

from functools import partial

bars.updateEvent += partial(onBarUpdate, contract)

def onBarUpdate(contract, bars, hasNewBar):
....