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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 plot_delta_m(fignum, B, DM, Bcr, s):
 """ function to plot Delta M curves Parameters __________ fignum : matplotlib figure number B : array of field values DM : array of difference between top and bottom curves in hysteresis loop Bcr : coercivity of remanence s : specimen name """

    plt.figure(num=fignum)
    plt.clf()
    if not isServer:
        plt.figtext(.02, .01, version_num)
    plt.plot(B, DM, 'b')
    plt.xlabel('B (T)')
    plt.ylabel('Delta M')
    linex = [0, Bcr, Bcr]
    liney = [old_div(DM[0], 2.), old_div(DM[0], 2.), 0]
    plt.plot(linex, liney, 'r')
    plt.title(s)