Make examples dynamic

[ulope]

With brython or similar

[pykong]

Eventually extending pyformat.info with a small fiddle would be great also. Akin to pythex, but for string formatting instead of regexes. Two input fields: One for value the other for the format string. Displaying result in output.

The exact same idea is implemented here for C#: https://www.code-sample.net/CSharp/Format-Number