On Stack Overflow, a user asked, "Should python-dev be required to install pip"? I think the answer to that is no, at least the way things are split up on most distros today. But there's clearly a potential for confusion for new developers, as the OP pointed out in a comment.
Part of the common wisdom among some OO fanatics is that Python isn't a real OO language because it "doesn't have encapsulation." There are a few different things that could mean, but none of them say anything useful.
The itertools module in the standard library comes with a nifty groupby function to group runs of equal values together.
Often, you have an algorithm that just screams out to use a dict for storage, but your data set is just too big to hold in memory. Or you need to keep the data persistently, but pickling or JSON-ing takes way too long.