If you are trying to emit the signal selectedInfoChanged then you would do as follows:
self.selectedInfoChanged.emit(packages, packagesSize, extraPackages, extraPackagesSize)
If you are trying to declare a signal with that signature then you would do the following:
class MyClass(QObject):
selectedInfoChanged=pyqtSignal(int, str, int, str)
Note: a signal must be a class attribute not an instance attribute and QString is not supported by PyQt5, just use python strings (PyQt5 automatically converts them to C++ QStrings).
Hope this helps ;-)