Finding the first occurrence in a collection of data is a common problem.
# Non Idiomatic found_line = None for line in logfile: if regex.match(line): found_line = line break return found_line
# Idiomatic return next(line for line in logfile if regex.match(line), None)
# Idiomatic (thanks to Suresh V) from itertools import dropwhile return next(dropwhile(lambda x: not regex.match(x), logfile), None)
The idiomatic solution is not only more compact, but it reads better.