I always forget how I should time little parts of my python code when I'm trying to optimize it, so I put it here so that I can just search for it later.
There's a bunch of timing functions in python: Some use various different clocks, but the Stack Exchange wisdom makes me want to use the timeit module.
.. codeblock:: python from timeit import default_timer as timer t_0 = timer() # here's some code b = 2 + 2 t_elapsed = timer() - t_0 print('Elapsed time = {t:4.4f} seconds.'.format(t=t_elapsed))