https://towardsdatascience.com/4-common-mistakes-python-beginners-should-avoid-89bcebd2c628

The article says beginner mistakes. That’s a bit harsh. I’ve been programming for nearly 20 years (admittedly only in Python properly for 5) and I got caught out by the default arguments being mutable. I was traversing a map, using a default argument and ended up traversing a map of 5 items about 16 times trying to visit each node once. Took me a while to figure out what was going on.

So this is more got A Level students, students who are embarking on larger projects where these points become useful.