Hey all,

Currently stuck on this problem, I read past forum posts about this, but it looks like my code is right, only difference being variable names. Here is what I have:

```
n = [[1, 2, 3], [4, 5, 6, 7, 8, 9]]
# Add your function here
def flatten(lists):
results = []
for numbers in lists:
for x in numbers:
results.append(x)
return results
print flatten(n)
```

Give me the error:

flatten([[1, 2], [3, 4]]) returned [1] instead of [1, 2, 3, 4]