As a beginning Python programmer, is it a good idea to build and understand my own libraries before jumping to advanced 3rd-party libraries that contains the functionality I need?
Some projects (e.g. web frameworks like Django) are probably too large for this approach. But other projects (e.g. Web Crawlers, graph libraries, HTML parser) seem to be feasible.
I worry that early reliance on 3rd-party libraries would stunt my growth.
Note: this question and this question seem to focus more an experienced programmers, who are probably more focused on the efficiency of reuse than the learning benefit. My question, I think, is focused on beginners.
Best Answer
This is always a trade-off.
As a beginning programmer, you should ask yourself two questions when considering reusing code vs. reinventing the square wheel:
If you don't have to finish your project, it's fine to spin your wheels on complex problems that other people have already solved, because you'll learn something. But you'll probably move on to something else before you "finish," which may or may not matter to you. Other projects will start to look shiny fast when you get in over your head on a complex domain that looks simple until you start trying to solve it yourself.
Don't obsess about giving up control because you're deferring to someone else's way of thinking; focus more on what you're trying to accomplish.
If your goal is to write an HTML parser because you want to understand how parsers work, go for it. If your goal is to write an HTML parser because you want to sanitize user input or transform some random bits of HTML, you're probably focused on the wrong thing, because you probably are more interested in the application of parsing rather than the parsing itself. If you feel like writing an HTML parser because you don't want to take time to understand someone else's library, you're probably wasting your time, because, at least in this case, I guarantee someone else has spent more time figuring out how to solve this problem effectively than you'll have. In really trivial cases, you may save time by not reusing code, but in complex ones, unless the library you use sucks or your ability to read documentation and code samples sucks, you'll just waste time.
On the other hand, I would say that it's worth writing your own graph library, since you'll be more focused on transferable, fundamental algorithms and data structures that you'll be able to apply to other domains, even if you end up using someone else's library when you work on those problems.