[Python] race condition issue in python

i want to consider following simple code :

from multiprocessing import Process,Value
import time
def add_10_times(number):
for i in range(10):
time.sleep(0.01)
number.value+=1
if __name__ =="__main__":
shared_number =Value('i',0)
process1 = Process(target=add_10_times, args=(shared_number,))
process2 = Process(target=add_10_times, args=(shared_number,))
process1.start()
process2.start()
process1.join()
process2.join()
print(f'final value is {shared_number.value}')


based on the following site : multiprocessing

and based on well known problem called as Race condition, value should be less then 20 right? but in most cases it gives me value 20 :

final value is 20


sometimes it jumps to 16 or 18 , but in most case it gives me 20, so where is Race condition? and under what case it occurs?

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