test.py

from Quartz import *

def MyFunction(*args):
	print args

tap = CGEventTapCreate(kCGHIDEventTap, kCGHeadInsertEventTap, kCGEventTapOptionListenOnly, kCGEventLeftMouseDown, MyFunction, None)

runLoopSource = CFMachPortCreateRunLoopSource(None, tap, 0)
CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource, kCFRunLoopDefaultMode)
CGEventTapEnable(tap, True)

print tap
print runLoopSource
#CFRunLoopRun()
CFRunLoopRunInMode(kCFRunLoopDefaultMode, 20, False)