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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 pretty_polyfit_plot(x, y, deg=1, xlabel=None, ylabel=None, **kwargs):
 """ Convenience method to plot data with trend lines based on polynomial fit. Args: x: Sequence of x data. y: Sequence of y data. deg (int):
 Degree of polynomial. Defaults to 1. xlabel (str):
 Label for x-axis. ylabel (str):
 Label for y-axis. \\*\\*kwargs: Keyword args passed to pretty_plot. Returns: matplotlib.pyplot object. """

    plt = pretty_plot(**kwargs)
    pp = np.polyfit(x, y, deg)
    xp = np.linspace(min(x), max(x), 200)
    plt.plot(xp, np.polyval(pp, xp), 'k--', x, y, 'o')
    if xlabel:
        plt.xlabel(xlabel)
    if ylabel:
        plt.ylabel(ylabel)
    return plt