Hi,

i tried this code first. obviously it didn't work. but i realized that i am not sure when to use "range" in the for function:

my initial code:

```
def product(number):
result = 1
for n in range(0,len(number)):
if n > 0:
result *= n
else: return "number is zero"
return result
print product([4, 5, 5])
```

then i removed the range portion to this:

```
def product(number):
result = 1
for n in number:
if n > 0:
result *= n
else: return "number is zero"
return result
print product([4, 5, 5])
```

i get the calculation parts correct but the error message is as follows:

"Oops, try again. Your function does not return an int."

then i removed the if and else condition to this :

```
def product(number):
result = 1
for n in number:
result *= n
return result
print product([4, 5, 5])
```

and i was able to pass.

so can some one please explain 1) when to use the "range" in for loop. 2) why my second code had that error.

Thank you.