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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 removeReference(self, fromnode, tonode):
 """ Remove all edges from fromnode to tonode """

        if fromnode is None:
            fromnode = self
        fromident = self.getIdent(fromnode)
        toident = self.getIdent(tonode)
        if fromident is not None and toident is not None:
            while True:
                edge = self.graph.edge_by_node(fromident, toident)
                if edge is None:
                    break
                self.graph.hide_edge(edge)