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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 mixin (cls):
 """ A decorator which adds event methods to a class giving it the ability to bind to and trigger events :param cls: the class to add the event logic to :type cls: class :return: the modified class :rtype: class """

    cls._events = {}
    cls.bind = Pyevent.bind.__func__
    cls.unbind = Pyevent.unbind.__func__
    cls.trigger = Pyevent.trigger.__func__
    return cls