What are the common Python errors people encounter?

I’m more of a Python hobbyist, but one mistake I often make is forgetting that in-place List methods return None. I try to chain them together, which leads to errors like "NoneType has no method named XXXX." It can be a real pain!

After 20+ years in coding, I can confidently say that calling methods with arguments out of order tends to trip me up, especially when I'm being lazy and not using keyword arguments. I’ve definitely written those methods, but I still forget sometimes!

With about 10 years of experience, I think mocking functions in the correct scope is one of the trickiest parts. If you get that wrong, it can lead to some frustrating bugs!

A common pitfall I've encountered is using default mutable arguments, like dictionaries or lists, and then mutating them later on. For example, if I define a function like `def go(foo={})`, it can lead to confusing results. Always a good idea to use immutable defaults!

In my experience with 4 years of Python, I’d say environment issues tend to cause the most problems for everyone, regardless of skill level. That's probably why many developers prefer using tools like virtual environments to streamline their work and minimize these headaches. Also, unexpected input leading to erratic behavior is a common issue with dynamically typed languages like Python.

With more than 20 years in the game, I’ve realized that the biggest error isn’t even technical—it's often the mindset of people who expect solutions handed to them without doing the legwork to solve problems. Just a little effort goes a long way!

Honestly, typos are my worst enemy! I’ve had a spellcheck running in my IDE since forever, and it still catches me off guard sometimes. They trip me up more often than I'd like to admit.