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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 circular_layout(nodes):
 """ Lay out nodes on a circle and add node index. """

    N = len(nodes)
    if not N:
        return ([], [], [])
    circ = np.pi/N*np.arange(N)*2
    x = np.cos(circ)
    y = np.sin(circ)
    return (x, y, nodes)