```
def digit_sum(n):
m = str(n)
final_product = 0
numbers = []
for c in m:
numbers.append(c)
for i in numbers:
l = 0
numbers[l] == int(i)
l = l + 1
for i in numbers:
final_product = final_product + i
```

Got the error message " Oops, try again. Does your digit_sum function take exactly one argument (a positive integer)? Your code threw a "unsupported operand type(s) for +: 'int' and 'str'" error." What am I doing wrong?