Catching a Key Error

There is a function foo$($n$)$ that takes an integer n does some calculations that involve dictionaries. Sadly, the people who wrote foo sometime look stuff up from the dictionary without checking if the key is in it first. This means the code sometimes throws a KeyError.

Write a function called safeFoo$($n$)$ that runs foo$($n$).$ If it runs successfully, it should return whatever foo returned. If it raises a KeyError, it should return None.

A sample Python run might look like this:

$>$ foo$(2)$ # This time it works

$20$

$>$ foo$(1)$ # This time it does not

Traceback $($most recent call last$)$:

File $"",$ line $1,$ in

KeyError: $\text{'}$x$\text{'}$

$>$ safeFoo$(1)$ # This will do the right thing.

None

Your code snippet should define the following variables:

Name Type Description

safeFoo function A function that safely calles foo