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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 categories_to_colors(cats, colormap=None):
 """ Map categorical data to colors. Parameters cats : pandas.Series or list Categorical data as a list or in a Series. colormap : list List of RGB triples. If not provided, the tableau20 colormap defined in this module will be used. Returns ------- legend : pd.Series Series whose values are colors and whose index are the original categories that correspond to those colors. """

    if colormap is None:
        colormap = tableau20
    if type(cats) != pd.Series:
        cats = pd.Series(cats)
    legend = pd.Series(dict(zip(set(cats), colormap)))
    # colors = pd.Series([legend[x] for x in cats.values], index=cats.index)
    # I've removed this output:
    # colors : pd.Series
    #     Series whose values are the colors for each category. If cats was a
    #     Series, then out will have the same index as cats.
    return(legend)