Advanced Views and URLconfs(The Definitive Guild to Django)

　　In Python regular expressions, the syntax for named regular expression groups is (?P<name>pattern), where name is the name of the group and pattern is some pattern to match.

　　If you put a single asterisk in front of a parameter in a function definition, any positional arguments to that function will be rolled up into a single tuple. If you put two asterisks in front of a parameter in a function definition, any keyword arguments to that function will be rolled up

into a single dictionary.