setChecked() pyQt doesn't appear to have any effect

So, I call it on my checkbox, I know that it's getting through the if statement because the box hides. I just want to also set it to false. And nothing happens.

created like so:

self.cb_openScene = WidgetBinding.QCheckBox(self.centralwidget)
self.cb_openScene.setObjectName(_fromUtf8("cb_openScene"))

Used like this:

self.cb_attMinifig.stateChanged.connect(self.cb_attMinifig_checkbox_changed)

def cb_attMinifig_checkbox_changed(self):
    if(self.cb_attMinifig.isChecked() == True):
        self.cb_openScene.setChecked(False)
        self.cb_openScene.hide()
    else:
        self.cb_openScene.show()

Any help as to why this has no effect at all on the checkbox would be great.

EDIT:

As requested

Ah yes, cb_attMinifig is a QCheckBox and WidgetBinding is

if(usingPySide):
    WidgetBinding = QtGui
    utfBinding = QtGui.QApplication.UnicodeUTF8
else:
    WidgetBinding = QtWidgets
    utfBinding = -1

This is to cover for use between Maya 2016 and Maya 2017 where the version of PySide is different.