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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 makediagram(edges):
 """make the diagram with the edges"""

    graph = pydot.Dot(graph_type='digraph')
    nodes = edges2nodes(edges)
    epnodes = [(node, 
        makeanode(node[0])) for node in nodes if nodetype(node)=="epnode"]
    endnodes = [(node, 
        makeendnode(node[0])) for node in nodes if nodetype(node)=="EndNode"]
    epbr = [(node, makeabranch(node)) for node in nodes if not istuple(node)]
    nodedict = dict(epnodes + epbr + endnodes)
    for value in list(nodedict.values()):
        graph.add_node(value)
    for e1, e2 in edges:
        graph.add_edge(pydot.Edge(nodedict[e1], nodedict[e2]))
    return graph