[raspasov]

(I use mostly Clojure)

It's not even only about the syntax. The Python environment, as far as I understand (and please correct me if I'm wrong), does not support re-definitions very well. Some things can be re-defined, but some cannot. So that's a problem in itself which makes REPL-driven development not very useful in Python.

[xapata]

Not sure why you'd say that. I redefine things often in Python.

[raspasov]

What about classes? Can you re-define those?

[xapata]

Not only can you redefine classes, you can change the class an object belongs to. Just point `obj.__class__` at something else, or change `cls.__bases__` to reorganize the class's inheritance hierarchy.

[nerdponx]

Yes, easily. Just re-execute the class definition code.