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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 histogram(values, bins=10, vrange=None, title="", c="g", corner=1, lines=True):
 """ Build a 2D histogram from a list of values in n bins. Use *vrange* to restrict the range of the histogram. Use *corner* to assign its position: - 1, topleft, - 2, topright, - 3, bottomleft, - 4, bottomright. .. hint:: Example: |fitplanes.py|_ """

    fs, edges = np.histogram(values, bins=bins, range=vrange)
    pts = []
    for i in range(len(fs)):
        pts.append([(edges[i] + edges[i + 1]) / 2, fs[i]])
    return xyplot(pts, title, c, corner, lines)