[Python] Generator that yields True a fixed number of times at random intervals before...

I want to iterate through a list of size n, with A 1s in it (the rest are 0s), and I want the 1s randomly distributed.
n and A are large, so I'm trying to make a generator instead of a list.
If they weren't super large, I might do indices=random.sample(range(N),A) and seq=[(i in indices) for i in range(N)].

My first thought was to do

from random import random
from math import log
n=355504839929
A=int(n*log(2,3))

def seq():
for i in range(n):
yield random()<A/n


On average this generator should yield True A out of n times. But I need it to be exactly A times.


Next I tried

def seq():
ones=0
for i in range(n):
if ones<A:
val=random()<A/n
ones+=val
yield val
else:
yield False


This way once it has produced A 1s it just yields False. But it's still possible to output fewer than A 1s.


Another thought I had is there are "n choose A" ways to arrange A 1s in the list, so I could choose a random value from range(math.comb(n,A)), and then write some generator that yields Trues according to the given combination. But if n is huge then "n choose A" is probably super huge and maybe not feasible to calculate.


Is there a way to do this?

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