Question: 
Write a function to find the nth delannoy number.


Model's Code:
def delannoy_num(m, n):
    D = [[0] * (n + 1) for _ in range(m + 1)]
    for i in range(m + 1):
        for j in range(n + 1):
            if i == 0 or j == 0:
                D[i][j] = 1
            else:
                D[i][j] = D[i - 1][j] + D[i][j - 1] + D[i - 1][j - 1]
    return D[m][n]



Sample Correct Code:
def dealnnoy_num(n, m): 
	if (m == 0 or n == 0) : 
		return 1
	return dealnnoy_num(m - 1, n) + dealnnoy_num(m - 1, n - 1) + dealnnoy_num(m, n - 1)


Asserts:
assert dealnnoy_num(3, 4) == 129
assert dealnnoy_num(3, 3) == 63
assert dealnnoy_num(4, 5) == 681


Tests:
Test 1 of 3: FAIL: NameError("name 'dealnnoy_num' is not defined")

Test 934 of 974: 716/934 (76.65952890792292%): failed