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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 copy_graph(subject, existing_graph):
 """Function takes a subject and an existing graph, returns a new graph with all predicate and objects of the existing graph copied to the new_graph with subject as the new subject Args: subject(rdflib.URIRef):
 A URIRef subject existing_graph(rdflib.Graph):
 A rdflib.Graph Returns: rdflib.Graph """

    new_graph = rdflib.Graph()
    for predicate, object_ in existing_graph.predicate_objects():
        new_graph.add((subject, predicate, object_))
    return new_graph