>>> x = []
>>> y = []
>>> 
>>> def test_loop():
...     for _ in range(5000000):
...         x.append(_)
... 
>>> def test_map():
...     map(y.append, range(5000000))
... 
>>> 
>>> import cProfile
>>> 
>>> cProfile.run('test_loop()')
         5000004 function calls in 0.842 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.595    0.595    0.842    0.842 <stdin>:1(test_loop)
        1    0.000    0.000    0.842    0.842 <string>:1(<module>)
  5000000    0.189    0.000    0.189    0.000 {method 'append' of 'list' objects}
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
        1    0.058    0.058    0.058    0.058 {range}


>>> cProfile.run('test_map()')
         5 function calls in 0.282 seconds>>> 

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        1    0.032    0.032    0.282    0.282 <stdin>:1(test_map)
        1    0.000    0.000    0.282    0.282 <string>:1(<module>)
        1    0.193    0.193    0.193    0.193 {map}
        1    0.000    0.000    0.000    0.000 {method 'disable' of '_lsprof.Profiler' objects}
        1    0.058    0.058    0.058    0.058 {range}