Hi. Sorry. Context is I broke my GUI and got it to a point where advice on another thread was to upgrade the kernel. An entire day of Googling and thread reading had me here. I followed the instructions in the prev post and got that error on running that line.
I agree it was too little info. Most people Google a lot and get very stressed before posting. I ended up doing a clean install, and now I'm having grief with that but I'll post separately.