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time.time() vs time.clock()

From a variety of sources, notably here, we have:

time.clock() gives the best timer accuracy on Windows, while the time.time() function gives the best accuracy on Unix/Linux.

Additionally on non 'win32' systems time.clock() will measure application CPU time, which excludes time spent waiting for I/O while time.time() will measure 'absolute' time. On win32 time.clock() also measures CPU time.

If you want to time your code and get absolute times, do what timeit does:

if sys.platform == "win32":
    # On Windows, the best timer is time.clock()
    default_timer = time.clock
else:
    # On most other platforms, the best timer is time.time()
    default_timer = time.time
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