In dynamic languages (like Python / Ruby / JS), you can use a debugger to jump into an interactive console (aka “REPL”) at any point in your code.

Here’s how to do it in Python 3:

1. edit your code

my_var = call_some_function() breakpoint()
add “breakpoint()”!

1. rerun your code (refresh the page, whatever)
2. play around in the REPL! You can call any function you want / try out fixes!

How to do it in other languages: - Ruby:
binding.pry - Python (before 3.7):
import pdb; pdb.set_trace() - Javascript:
debugger;