Oops, try again.

factorial(1) resulted in an error: invalid literal for int() with base 10: ''

it works like it supposed to

```
def factorial(x):
x = int(raw_input("Enter a number: "))
l = range(1, x+1)
result = 1
if x == 0:
return result
elif x > 0:
for number in l:
result = result * number
return result
else:
print("mathematically impossible !!")
print factorial(x)
```