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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 imshow_z(data, name):
 """2D color plot of the quasiparticle weight as a function of interaction and doping"""


    zmes = pick_flat_z(data)

    plt.figure()
    plt.imshow(zmes.T, origin='lower', \
            extent=[data['doping'].min(), data['doping'].max(), \
            0, data['u_int'].max()], aspect=.16)
    plt.colorbar()
    plt.xlabel('$n$', fontsize=20)
    plt.ylabel('$U/D$', fontsize=20)
    plt.savefig(name+'_imshow.png', dpi=300, format='png',
            transparent=False, bbox_inches='tight', pad_inches=0.05)