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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 _AddDependencyEdges(self, rdf_artifact):
 """Add an edge for every dependency of the given artifact. This method gets the attribute names for a given artifact and for every attribute it adds a directed edge from the attribute node to the artifact node. If an artifact does not have any dependencies it is added to the set of reachable nodes. Args: rdf_artifact: The artifact object. """

    artifact_dependencies = artifact_registry.GetArtifactPathDependencies(
        rdf_artifact)
    if artifact_dependencies:
      for attribute in artifact_dependencies:
        self._AddEdge(attribute, rdf_artifact.name)
    else:
      self.reachable_nodes.add(rdf_artifact.name)
      self.graph[rdf_artifact.name].is_provided = True