C API for modules

[John Machin]

"Edward C. Jones" <edcjones at erols.com> wrote in message news:<3CA09F43.80206 at erols.com>...
> Is there some simple way to call functions in modules from C? In 
> particular, for module struct, how do I call pack, unpack, and calcsize?
> 

OK, I'll be the bunny and ask the obvious(?) meta-question:

Give that the struct module is designed for Python callers to
pack/unpack C structs (laboriously), why bother? Why not just
manipulate the structs in C??