Question about code writing '% i, callback'

[Ian Kelly]

On Mon, Nov 30, 2015 at 7:44 PM, Dennis Lee Bieber
<wlfraed at ix.netcom.com> wrote:
> On Mon, 30 Nov 2015 10:55:23 -0800 (PST), fl <rxjwg98 at gmail.com> declaimed
> the following:
>
>>Thanks Ian. I created the class because I want to use the original example
>>line
>>
>> UI.Button("button %s" % i, callback)
>>
>>Is there another way to use the above line without my class definition?
>>I do feel that my created class does not match well with the above line
>>because the first item "button %s" does not fit __self__ in the class.
>
>         The first item passed to a method call is the instance object... In
> this case, whatever "UI" is bound to.
>
>         If it helps, think of
>
>                 UI.Button("string", callback)
> as
>                 Button(UI, "string", callback)

This is only correct if "UI" is bound to an instance of a class and
"Button" is a method of that class. If UI is a class itself or a
module, then those are not equivalent.