import System
clr.AddReference("C:\\Program Files\\Zebra Technologies\\Barcode Scanners\\Scanner SDK\\Scanner SDK\\Sample Applications\\bin\\Interop.CoreScanner.dll")
from CoreScanner import * 
import CoreScanner 

cs = CCoreScanner() # initialize scanner
status = -1
xml = ''
cs.Open(0, System.Array[System.Int16]([1]), 1, status) # open connection to scanner

subscribe_xml = '<inArgs><cmdArgs><arg-int>6</arg-int><arg-int>1,2,4,8,16,32</arg-int></cmdArgs></inArgs>'
print(cs.ExecCommand(1001, subscribe_xml, xml, status)) # subscribing to scanner events

def func(*args): # this is my event function
    print(args)

    #return True   # silently fails and will not fire on scan ever again
    return "OK"    # works fine, event fires every scan

cs.BarcodeEvent += CoreScanner._ICoreScannerEvents_BarcodeEventEventHandler(func) # add event to the event chain
# <class 'CLR.EventBinding'>