Simple generic functions (similar to Python's own len(), pickle.dump(), etc.)
Description
The simplegeneric module lets you define simple single-dispatch generic
functions, akin to Python's built-in generic functions like len(), iter() and
so on. However, instead of using specially-named methods, these generic
functions use simple lookup tables, akin to those used by e.g. pickle.dump()
and other generic functions found in the Python standard library.
