I posted two files, the first is twi_defines.h, the second was the sketch. If you copied both to the sketch, just delete the line `#include “twi_defines.h”.
To set the port for uploading, edit the platformio.ini file and add something like upload_port = /dev/ttyUSB0, or similar port name. See Redirecting... for full detail.
Cheers,
Norm.