Even dumber idea

a = [[1,2,0,4,5,6,7,0,9],
        [1,2,11,4,5,6,7,8,9],
        [1,1,3,4,5,5,41,8,9],
        [1,4,1,4,5,6,7,8,9],
        [1,2,3,4,5,11,7,8,9]]










def average(a,w,h):
    c=[]
    for y in range(0,h):
        l=[]
        m=[a[0][0],a[1][0]]
        r=[a[0][1],a[1][1]]
        R=[]
        for x in range(1, w+1):
            R.append((int)((sum(l)+sum(m)+sum(r))/(len(l)+len(m)+len(r))))
            l=m
            m=r
            r=[]
            for i in range(y-1,y+2):
                if i >= 0 and i < h and x+1 < w:
                    r.append(a[i][x+1])
        c.append(R)
    return c











avr = average(a, 9, 5)

print ("a: ")
for R in a:
    print (R)


print ("\n\n\naverage: ")
for R in avr:
    print (R)