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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 getAllNodeUids(self):
        '''
            getAllNodeUids - Gets all the internal uids of all nodes, their children, and all their children so on..

              @return set<uuid.UUID>
        '''
        ret = set()

        for child in self:
            ret.update(child.getAllNodeUids())

        return ret