[Python] How to use lock as a mutex in multiprocessing?

I want to have two processes, one writing and one reading on/from the same variable. The data written is like this:

[0, 0]
[0, 1]
[1, 0]
[1, 1]
[2, 0]
[2, 1]
[3, 0]
[3, 1]
[4, 0]
[4, 1]
[5, 0]
[5, 1]
[6, 0]
[6, 1]
[7, 0]
[7, 1]
[8, 0]
[8, 1]
[9, 0]
[9, 1]


But I'm having trouble because the reading process is reading between the variable change, forming new pairs, so I want to use a Lock/Mutex to prevent this from happening again. I guess I'd have to lock the object before changing it. OBS: The object is shared between processes using a manager.

Here is the main code:

import multiprocessing

def mde(dad, mutex):
for i in range(10):
for j in range(2):
mutex.acquire()
dad[0] = i
dad[1] = j
mutex.release()
def mda(dad):
c = 0
while c < 30:
print(dad)
c += 1

if __name__ == '__main__':
manager = multiprocessing.Manager()
mutex = manager.Lock()
dado = manager.list([0, 0])
p1 = multiprocessing.Process(target=mde, args=(dado, mutex,))
p2 = multiprocessing.Process(target=mda, args=(dado,))
p1.start()
p2.start()
p1.join()
p2.join()


As you can see I tried to lock and unlock the variable in the writing process but the result still was mixed up. What am I doing wrong?

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