How can I hook PrtSc key?

[mikezang]

I tried to hook print screenshot key in Python, I did as below in file CvEventmanager.py:

	if (theKey == int(InputTypes.KB_SYSRQ) and self.bAlt):
		self.beginEvent(CvUtil.EventCustomLogEntry)
		return 1

But it seems like not wokring, does anyone help me?