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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def addHandlerClass(clazz):
 """Register handler class."""

    if not issubclass(clazz, EventHandler):
        raise ValueError("%s must be subclassed from %s" % (clazz, EventHandler))
    _handler_classes[clazz.name] = clazz