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# what's wrong with it?

def add(x, y): return(float(x) + float(y)) try: add(x, y) except ValueError: return(none) else: return(add(x, y))

trial.py
```def add(x, y):
return(float(x) + float(y))
try:
except ValueError:
return(none)
else:
```

STAFF

Hi oliverchou ! You did great right up until the last step. And even then, you're not that far off. One thing to note though, it's generally not a good idea for a function to call itself. This can lead to infinite recursion. Let me show you my solution and then walk you through what it's doing:

```def add(x, y):
try:
return float(x) + float(y)
except ValueError:
return None
```

Our add function is going to accept two inputs. Now, we hope that they are numbers. But users are unpredictable and make typos sometimes. So we want to make sure that what they put in, is actually a number.

So first we `try` to convert both inputs into floats. If that works, we add them together and return the result. However, if we get an exception of `ValueError` (this means the user typed in something like E and 2) then we return `None`. Hope this helps!

Got it! just simply put all script into that "add" function thanks! :)