If you are initializing an i2c device and you are keep getting the following output: i2c_writeBufferRaw: symbol not found, please do not panic as it is a very easy fix. Since the old version of i2c library did not have a specific function that allows reading without specifying address, a new version of the I2C library contains that function. To solve this, simply issue following commands:

opkg update
opkg upgrade libonioni2c pyOnionI2C


And that is it!