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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 toc(self):
 """ Returns a rich list of texts in the catalog. """

        output = []
        for key in sorted(self.catalog.keys()):
            edition = self.catalog[key]['edition']
            length = len(self.catalog[key]['transliteration'])
            output.append(
                "Pnum: {key}, Edition: {edition}, length: {length} line(s)".format(
                    key=key, edition=edition, length=length))
        return output