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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(hdiff, title):
 """ Plots the tropical solar length by year. """

    import matplotlib.pyplot as plt
    years = [elem[0] for elem in hdiff]
    diffs = [elem[1] for elem in hdiff]
    plt.plot(years, diffs)
    plt.ylabel('Distance in minutes')
    plt.xlabel('Year')
    plt.title(title)
    plt.axhline(y=0, c='red')
    plt.show()