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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 dataframe(self):
 """ Returns a ``pandas DataFrame`` containing all other relevant class properties and values where each index is a different season plus the career stats. """

        temp_index = self._index
        rows = []
        indices = []
        if not self._season:
            return None
        for season in self._season:
            self._index = self._season.index(season)
            rows.append(self._dataframe_fields())
            indices.append(season)
        self._index = temp_index
        return pd.DataFrame(rows, index=[indices])