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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 addHost(self, name=None):
        '''
        Add a new host node to the topology.
        '''
        if name is None:
            while True:
                name = 'h' + str(self.__hnum)
                self.__hnum += 1
                if name not in self.__nxgraph:
                    break
        self.__addNode(name, Host)
        return name