In [4]:

    

import dis
import math


    

In [7]:

    

def func(n):
    x = 0
    for i in range(n):
        x += i
    return x 

dis.dis(func)


    

    




  2           0 LOAD_CONST               1 (0)
              3 STORE_FAST               1 (x)

  3           6 SETUP_LOOP              30 (to 39)
              9 LOAD_GLOBAL              0 (range)
             12 LOAD_FAST                0 (n)
             15 CALL_FUNCTION            1 (1 positional, 0 keyword pair)
             18 GET_ITER
        >>   19 FOR_ITER                16 (to 38)
             22 STORE_FAST               2 (i)

  4          25 LOAD_FAST                1 (x)
             28 LOAD_FAST                2 (i)
             31 INPLACE_ADD
             32 STORE_FAST               1 (x)
             35 JUMP_ABSOLUTE           19
        >>   38 POP_BLOCK

  5     >>   39 LOAD_FAST                1 (x)
             42 RETURN_VALUE