QMapIterator::Item is private

QMap<QString, int> map;
QMapIterator<QString, int> it = map;
auto item1 = it.next(); // it works!
QMapIterator<QString, int>::Item item2 = it.next(); // compilation error

../main.cpp: In function ‘int main(int, char**)’:
../main.cpp:35:33: error: ‘typedef QMapIterator<QString, int>::const_iterator QMapIterator<QString, int>::Item’ is private within this context
 QMapIterator<QString, int>::Item item2 = it.next();
 ^~~~
In file included from /usr/include/qt5/QtCore/qlist.h:44,
 from /usr/include/qt5/QtCore/QList:1,
 from ../json.h:3,
 from ../main.cpp:1:
/usr/include/qt5/QtCore/qmap.h:1290:1: note: declared private here
 Q_DECLARE_ASSOCIATIVE_ITERATOR(Map)
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~