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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 event_handler(msg: EventMsgDict) -> Event: """Handle events emitted on browser."""

    e = create_event_from_msg(msg)
    if e.currentTarget is None:
        if e.type not in ['mount', 'unmount']:
            id = msg['currentTarget']['id']
            logger.warning('No such element: wdom_id={}'.format(id))
        return e
    e.currentTarget.on_event_pre(e)
    e.currentTarget.dispatchEvent(e)
    return e