1if the object o provides numeric protocols, and false otherwise. This function always succeeds.
*p2have the same type, increment their reference count and return
0(success). If the objects can be converted to a common numeric type, replace
*p2by their converted value (with 'new' reference counts), and return
0. If no conversion is possible, or if some other error occurs, return
-1(failure) and don't increment the reference counts. The call
PyNumber_Coerce(&o1, &o2)is equivalent to the Python statement "o1, o2 = coerce(o1, o2)".