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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 describe(self):
 """ Describes this Categorical Returns ------- description: `DataFrame` A dataframe with frequency and counts by category. """

        counts = self.value_counts(dropna=False)
        freqs = counts / float(counts.sum())

        from pandas.core.reshape.concat import concat
        result = concat([counts, freqs], axis=1)
        result.columns = ['counts', 'freqs']
        result.index.name = 'categories'

        return result