Below is our original temperature converting program.

In [16]:

```
def temp_conv():
celsius = float(input("What is the celsius temperature? "))
fahrenheit = 9/5 * celsius + 32
print("The temperature is {0} degrees Fahrenheit.".format(fahrenheit))
```

In [17]:

```
temp_conv()
```

Now, let's add warnings for the cases of if the temperature in Fahrenheit is too hot (>= 90°F) or too cold (<= 30°F).

We use two *simple conditions*, where a condition is checked and only executed if the condition is evaluated to `True`

.

The one dissadvantage of simple conditions is that redundant, mutually-exclusive conditions are all executed. It the `fahrenheit`

is `190`

, it doesn't make sense to check if `fahrenheit >= 90`

*and* `fahrenheit <= 30`

(it's impossible to be both greater than 90° and less than 30° at the same time).

There is no harm in doing this in this simple program, but we will learn better techniques with two-way and multi-way decisions.

In [13]:

```
def temp_conv2():
celsius = float(input("What is the celsius temperature? "))
fahrenheit = 9/5 * celsius + 32
print("The temperature is {0} degrees Fahrenheit.".format(fahrenheit))
if fahrenheit >= 90:
print("It's really hot outside, get a lemonade.")
if fahrenheit <= 30:
print("It's really cold outside, get a hot chocolate.")
```

In [14]:

```
temp_conv2()
```

In [15]:

```
temp_conv2()
```