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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 fetch(self):
 """Implements Munin Plugin Fetch Option. Prints out measured values. """

        self.retrieveVals()
        for parent_name in self._graphNames:
            graph = self._graphDict[parent_name]
            if self.isMultigraph:
                print "multigraph %s" % self._getMultigraphID(parent_name)
            print self._formatVals(graph.getVals())
            print
        if (self.isMultigraph and self._nestedGraphs 
            and self._subgraphDict and self._subgraphNames):
            for (parent_name, subgraph_names) in self._subgraphNames.iteritems():
                for graph_name in subgraph_names:
                    graph = self._subgraphDict[parent_name][graph_name]
                    print "multigraph %s" % self.getMultigraphID(parent_name, 
                                                                 graph_name)
                    print self._formatVals(graph.getVals())
                    print
        return True