This is my python `hello.py` script:

```
def hello(a,b):
    print "hello and that's your sum:"
    sum=a+b
    print sum
    import sys

if __name__ == "__main__":
    hello(sys.argv[2])

```

The problem is that it can't be run from the windows command line prompt, I used this command:

```
C:\Python27>hello 1 1

```

But it didn't work unfortunately, may somebody please help?