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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 _add_monitor(monitors, handle, callback, devices, events):
 """Add the given monitor to the listed devices and events."""


    for conn_string in devices:
        data = monitors.get(conn_string)
        if data is None:
            data = dict()
            monitors[conn_string] = data

        for event in events:
            event_dict = data.get(event)
            if event_dict is None:
                event_dict = dict()
                data[event] = event_dict

            event_dict[handle] = callback