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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 get_dependency_graph(self):
 """Generate the dependency graph. The dependency graph is a simpler subset of the resolve graph. It contains package name nodes connected directly to their dependencies. Weak references and conflict requests are not included in the graph. The dependency graph does not show conflicts. Returns: `pygraph.digraph` object. """

        from rez.vendor.pygraph.classes.digraph import digraph

        nodes = {}
        edges = set()
        for variant in self._resolved_packages:
            nodes[variant.name] = variant.qualified_package_name
            for request in variant.get_requires():
                if not request.conflict:
                    edges.add((variant.name, request.name))

        g = digraph()
        node_color = "#AAFFAA"
        node_fontsize = 10
        attrs = [("fontsize", node_fontsize),
                 ("fillcolor", node_color),
                 ("style", "filled")]

        for name, qname in nodes.iteritems():
            g.add_node(name, attrs=attrs + [("label", qname)])
        for edge in edges:
            g.add_edge(edge)
        return g