PK_ERROR_code_t    PK_PART_ask_groups
(
--- received arguments ---
PK_PART_t          part,            --- a part

--- returned arguments ---
int         *const n_groups,    --- number of groups (>=0)
PK_GROUP_t **const groups       --- groups (optional)
)


This function returns the set of groups contained within the given part.


The output array groups is optional. If it is set to NULL, the function
will only compute the number of groups in the part.