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    Lab 3: Conditional Expressions
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Consider the function `category` that takes an integer and returns a single string
indicating whether it's even or odd and whether it's negative or not: 

```python
def category(n):
    if n%2 == 0:
        evenOrOdd = 'even'
    else:
        evenOrOdd = 'odd'
    if n < 0:
        negOrNot = 'neg'
    else:
        negOrNot = 'nonneg'
    return f"{evenOrOdd} {negOrNot}"
```
For example:
```
>>> category{17}
'odd nonneg'

>>> category{-42}
'even neg'
```

The body of `category` uses two conditional **statements**, each of which uses the result
of a _test expression_ to to choose beween
executing a _then branch statement sequence_ or an _else branch statement sequence_.

```python
if testExp:
    thenBranchStm_1
    ...
    thenBranchStm_m
else:
    elseBranchStm_1
    ...
    elseBranchStm_n

But Python (and most other programming languages) also has a
conditional **expression** construct that uses the result of a
_test expression_ to to choose beween the result of evaluating
a _then branch expression_ or an _else branch expression_:

```python
thenBranchExp if testExp then elseBranchExp
```

It turns out that **expressions** are typically more flexible and
powerful than **statements**, so you are strongly encoraged to
use conditional **expressions** rather than conditional **statements**
in situations where they are sensible.

Here is one way to use conditional expressions to implement
a version of the `category` function above:

```python


```




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