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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_plate_limits(axis, ridges, trenches, ymin, ymax):
 """plot lines designating ridges and trenches"""

    for trench in trenches:
        axis.axvline(
            x=trench, ymin=ymin, ymax=ymax,
            color='red', ls='dashed', alpha=0.4)
    for ridge in ridges:
        axis.axvline(
            x=ridge, ymin=ymin, ymax=ymax,
            color='green', ls='dashed', alpha=0.4)
    axis.set_xlim(0, 2 * np.pi)
    axis.set_ylim(ymin, ymax)