I want to combine these two loops into one, but I'm concerned t would be slower if it had to check the boolean `is_fahrenheit` in every iteration.

```
if is_fahrenheit:
    for c in cities_list:
        degree_fahrenheit = round((c.degrees - 273.15) * (9/5) + 32)
        weather_info = {'id': c.id, 'city': c.name, 'degrees': degree_fahrenheit, 'state': c.state, 'time_of_day': c.time_of_day}
        cities_info.append(weather_info)
else:
    for c in cities_list:
        degree_celsius = round(c.degrees - 273.15)
        weather_info = {'id': c.id, 'city': c.name, 'degrees': degree_celsius, 'state': c.state, 'time_of_day': c.time_of_day}
        cities_info.append(weather_info)

```

How can I best do this?