python 3: sorting with a comparison function

[Terry Reedy]

Kay Schluehr wrote:

> Me too because I don't get this:
> 
> "key specifies a function of one argument that is used to extract a
> comparison key from each list element: key=str.lower. The default
> value is None."

I am not sure what you do not get, but it should say 'for example, 
key=str.lower."  None is the default value of key.