[Tutor] Fahrenheit to Celsius Conversion another problem and Programming Paradigm

[Peter Otten]

Sebastian Silva wrote:

> Or shorter:
> 
> if unit in 'Cc':

Don't do that. You are in for nasty surprises: 

>>> def check(unit):
...     if unit in "Cc":
...         return "Celsius"
...     return "unknown"
... 
>>> check("c")
'Celsius'
>>> check("C")
'Celsius'
>>> check("F")
'unknown'

Fine so far. But now:

>>> check("Cc")
'Celsius'
>>> check("")
'Celsius'