def _get_duped_varnodes(self):
        srcmap = {}
        allsrcs = set()
        for node, data in self.nodes_iter(data=True):
            if 'comp' not in data:
                if isinstance(node, tuple):
                    allsrcs.add(node[0])

        for node, data in self.nodes_iter(data=True):
            if 'comp' not in data:
                if isinstance(node, tuple):
                    srcmap.setdefault(node[0], set()).add(node)
                    # check dests for any sources.  this can happen with
                    # parameters
                    for dest in node[1]:
                        if dest in allsrcs:
                            srcmap.setdefault(dest, set()).add(node)

        for src, nodes in srcmap.items():
            if len(nodes) < 2:
                del srcmap[src]

        return srcmap
Handle one request at a time until told to stop.
dataset/ETHPy150Open OpenMDAO/OpenMDAO-Framework/openmdao.main/src/openmdao/main/depgraph.py/CollapsedGraph._get_duped_varnodes--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/dev_appserver.py/HTTPServerWithScheduler.serve_forever