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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 columns_by_index(self) -> Dict[str, List[Well]]: """ Accessor function used to navigate through a labware by column name. With indexing one can treat it as a typical python dictionary. To access row A for example, simply write: labware.columns_by_index()['1'] :return: Dictionary of Well lists keyed by column name """

        col_dict = self._create_indexed_dictionary(group=2)
        return col_dict