can't solve an exercise-help me with it

[Bengt Richter]

On Thu, 12 Jan 2006 05:51:10 +0100, "hossam" <nono at hotmail.com> wrote:

>I'm studying python newly and have an exercise that is difficult for me as a 
>beginner.Here it is :
>"Write a program that approximates the value of pi by summing the terms of 
>this series:
>4/1-4/3+4/5-4/7+4/9-4/11+.... The program should prompt the user for n, the 
>number of terms to sum and then output the sum of the first n terms of this 
>series."
>
>any help would be appreciated.
>
Is this homework?
What have you tried so far?
Hints: raw_input, int. And sum, if you want a one-liner.
Hint2: try 4/7 and 4.0/7 interactively

Regards,
Bengt Richter