Build hostnames with a default environment

Write a function make_hostname(role, number, env="prod") that returns a hostname like prod-web-03. The number is always shown with two digits. If env is not given, it defaults to "prod". Print the result of the two calls in the examples.

Parameters can have default values, written as env="prod" in the def line. If the caller leaves that argument out, the default is used; if they pass a value, it replaces the default. Parameters with defaults must come after those without. To pad the number, use a format specifier inside the f-string: {number:02d} means "show as a whole number, at least 2 characters wide, padded with zeros". The function returns the finished string so the caller can print it or use it elsewhere.