Thank you guys!
Actually I already made a dock with the BME280 sensor.
I was porting it from raspberry to Onion, and it seems It will need more recoding than I thought since smbus is not working, but calling the i2ctools I think I will be able to make it work.

Thanks!

It would be really useful to be able to handle I2C in Python, is there any work around about this?

Thank you!