code: func (v *Entry) GetBuffer() (*EntryBuffer, error) {
  	c := C.gtk_entry_get_buffer(v.native())
  	if c == nil {
  		return nil, nilPtrErr
  	}
  	obj := glib.Take(unsafe.Pointer(c))
  	return &EntryBuffer{obj}, nil
  }
docs: // GetBuffer() is a wrapper around gtk_entry_get_buffer().