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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 list_connections(self, limit=500, offset=0):
 """List Points to which this Things is subscribed. I.e. list all the Points this Thing is following and controls it's attached to Returns subscription list e.g. #!python { "<Subscription GUID 1>": { "id": "<Control GUID>", "entityId": "<Control's Thing GUID>", "type": 3 # R_CONTROL from IoticAgent.Core.Const }, "<Subscription GUID 2>": { "id": "<Feed GUID>", "entityId": "<Feed's Thing GUID>", "type": 2 # R_FEED from IoticAgent.Core.Const } Raises [IOTException](./Exceptions.m.html#IoticAgent.IOT.Exceptions.IOTException) containing the error if the infrastructure detects a problem Raises [LinkException](../Core/AmqpLink.m.html#IoticAgent.Core.AmqpLink.LinkException) if there is a communications problem between you and the infrastructure Note: For Things following a Point see [list_followers](./Point.m.html#IoticAgent.IOT.Point.Point.list_followers) """

        evt = self._client._request_sub_list(self.__lid, limit=limit, offset=offset)

        self._client._wait_and_except_if_failed(evt)
        return evt.payload['subs']