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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_covariance_ellipse( mean, cov=None, variance=1.0, std=None, ellipse=None, title=None, axis_equal=True, show_semiaxis=False, facecolor=None, edgecolor=None, fc='none', ec='#004080', alpha=1.0, xlim=None, ylim=None, ls='solid'):
 """ Deprecated function to plot a covariance ellipse. Use plot_covariance instead. See Also -------- plot_covariance """


    warnings.warn("deprecated, use plot_covariance instead", DeprecationWarning)
    plot_covariance(mean=mean, cov=cov, variance=variance, std=std,
                    ellipse=ellipse, title=title, axis_equal=axis_equal,
                    show_semiaxis=show_semiaxis, facecolor=facecolor,
                    edgecolor=edgecolor, fc=fc, ec=ec, alpha=alpha,
                    xlim=xlim, ylim=ylim, ls=ls)