pub unsafe extern "C" fn igraph_is_eulerian(
graph: *const igraph_t,
has_path: *mut igraph_bool_t,
has_cycle: *mut igraph_bool_t,
) -> igraph_error_tpub unsafe extern "C" fn igraph_is_eulerian(
graph: *const igraph_t,
has_path: *mut igraph_bool_t,
has_cycle: *mut igraph_bool_t,
) -> igraph_error_t