Qt C++ implements operator== for QKeyEvent == QKeySequence and QKeySequence ==
QKeyEvent.

Analogously, PyQt implements QKeyEvent.__eq__() and QKeyEvent.__ne__().
But PySide does not.

(PyQt also implements len() and a raft of other comparison operators for
QKeyEvent; I did not check to see if these were in PySide.)

My workaround is to use QKeyEvent.matches(). It was a bit confusing that I
could of course use ==, but it was not actually testing what I expected.

Interactive test program: When you run this and then type Ctrl+C, you'll get an
event when you hold down Ctrl, and then again when you press C.

#--------------------------
from PyQt4.QtCore import *
from PyQt4.QtGui import *
#from PySide.QtCore import *
#from PySide.QtGui import *

class MyLabel(QLabel):
    def keyPressEvent(self, key_event):
        print "key_event.matches(QKeySequence.Copy):",
key_event.matches(QKeySequence.Copy)
        print "key_event == QKeySequence.Copy:", key_event == QKeySequence.Copy
        print "QKeySequence.Copy== key_event:", QKeySequence.Copy == key_event
        print
        key_event.accept()

app = QApplication([])
w = MyLabel('Try Ctrl+C on this widget')
w.show()
app.exec_()