I am getting a pop-up error message in the right hand corner of my Databricks session, "Your notebook session has crashed."  This is a notebook I've been working in for a while.

The only line of code I am running is 

pip list

The error at the bottom of my notebook when I run this code is, "Failure starting repl. Try detaching and re-attaching the notebook or clearing the notebook environment."

I have tried the following to fix this and they have not worked:

• Starting a new session.
• Terminating the session and starting a new one.
• Terminating the session, closing the notebook, reopening the notebook, starting a new session.

I have run the "pip list" code in a new notebook and it run just fine.

Why am I getting this error?  How do I fix it and continue to work in my notebook?

Thank you!