How to shorten and optimize the algorithm?

Question

Python

I am solving the 23rd problem from the Euler project, I solved it in a rather greedy way, so greedy that I did not wait for the result ...
I ask you to help me reduce the code and optimize it, because after looking at other people's solutions, I understood the code, but did not understand why they did it some of the actions.

def izb(n:int):
    delt = []
    for i in range(1,n):
        if n % i == 0:
            delt.append(i)
    else:
        if sum(delt) > n:
            return True
        else:
            return False

def allizb():
    all_izb = []
    for i in range(12,28124):
        if izb(i) == True:
            all_izb.append(i)
    else:
        return all_izb

alizb = allizb()

i = 1 
otv = []

for i in range(12,28124):
    for g in alizb:
        for h in alizb:
            if i != (g+h):
                otv.append(i)
            print(i)
else:
    print( sum(otv ))

Answer 1

you can see here you
can use nimpy (uses NIM), pypy (JIT), Cython (C code compiles your program).
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