Python: split a list based on a condition?

Question

What\'s the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:

Answer 1

good.append(x) if x in goodvals else bad.append(x)

This elegant and concise answer by @dansalmo showed up buried in the comments, so I'm just reposting it here as an answer so it can get the prominence it deserves, especially for new readers.

Complete example:

good, bad = [], []
for x in my_list:
    good.append(x) if x in goodvals else bad.append(x)