[brudgers]

After fooling around with porting some Common Lisp code to Python as an exercise in reinforcing my understanding of the underlying algorithms and learning Python, I would describe the difference as the Python interpreter was mostly designed with the assumption that the typical use case would be executing the interpreter with a source file as an argument [e.g. python spam.py] and not primarily as an interactive development tool that is left as a running process for days or weeks. Instead Python ships with IDLE which more reflects the idea of an interpreter running source files serially.

Or to put it another way, trace is an option that is passed to the Python interpreter. In Common Lisp (trace ...) is a function that can be called in the REPL.

[BeetleB]

The standard Python interpreter is crap. One should use IPython. I'd like to see a comparison with that one.

[dangerbird2]

The standard repl for Steel Bank Common Lisp is worse than Cpython's with no basic readline support. The Common Lisp environment really shows its strengths when using a fully interactive development environment like a Lisp machine environment or Emacs with SLIME.

[omaranto]

I'd call it the "built-in repl" rather than the standard one, since I don't think it's actually standard for people to use it directly.

[lispm]

CLISP has readline support.

[patrickg_zill]

That is exactly correct. Guido van Rossum's original paper on a scripting language called ABC which strongly influenced his later design of Python, was basically a scripting language for system administration tasks on Unix and Unix-like operating systems.