How do I get time of a Python program's execution?

I have a command line program in Python that takes a while to finish. I want to know the exact time it takes to finish running.

I've looked at the timeit module, but it seems it's only for small snippets of code. I want to time the whole program.

The simplest way in Python:

import time
start_time = time.time()
main()
print("--- %s seconds ---" % (time.time() - start_time))

This assumes that your program takes at least a tenth of second to run.

Prints:

--- 0.764891862869 seconds ---

Stack Overflow Q#1557571, score: 3118