Referencing a conditional random element of an array and replacing it

This is my second question post on StackOverflow relating to coding in Python/Numpy.

I feel like there is definitely some sort of function which does the pseudocode:

np.random.choice([a[i-1,j],a[i+1,j],a[i,j-1],a[i,j+1]])==0 = 9

Essentially, I would like the random function to select a cell adjacent to mine (up, down, left, right) with the value 0, and replace said cell with a 9

Unforunately, I know why the code I typed is illegal. The first half of the statement returns a True/False boolean as I have used a comparison/checking operator. I can't set this into a value 9.

If I split the code-load into two codes and used an if statement with the random.choice (looking at an adjacent element that equalled zero), then following this, I would need some sort of function or definition to recall which cell (up down left or right) did the random generator originally select, to which I can then set it to 9.

Kind Regards,

EDIT: I may as well attach a sample code, so you can simply just run this (I am including my error)

a = np.empty((6,6,))
a[:] = 0
a[2,3]=a[3,3]=a[2,4] = 1

for (i,j), value in np.ndenumerate(a):
     if a[i,j]==1:
          np.random.choice([a[i-1,j],a[i+1,j],a[i,j-1],a[i,j+1]])==0 = 9