https://sumitkgaur.wordpress.com/2014/05/13/python-debugging/

sudo apt update
sudo apt install -y python3-dbg oython3-dev

more /usr/share/doc/python3-dbg/README.debug 
Have the libraries run automatically:

### Note your python version might be different (like 3.5 or 3.8)
### just see what the package was installed at from above
zcat /usr/share/doc/python3.7/gdbinit >> ~/.gdbinit


gdb -p 455

Or run the libraries at load: (doesn't work)
gdb --args python3-dbg 455

Run on a script:
gdb ~/myscript.py

Process will most likely stop, so you can hit c to continue for a bit and ctrl-C to stop again


    py-bt — Get stack trace of the python process
    info threads — If one process has more than one thread, you can find the list of all threads executing.
    py-list — Find out the code which the current thread is executing
    py-down — Select and print the python stack frame called by this one (if any)
    py-up — Select and print the python stack frame that called this one (if any)
    py-locals — Get all python local variables in the current frame
    py-print — Look up the given python variable name
    
    
    next
    next
    finish