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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 get_group_for_col(self, table_name, col_name):
 """ Check data model to find group name for a given column header Parameters table_name: str col_name: str Returns --------- group_name: str """

        df = self.dm[table_name]
        try:
            group_name = df.loc[col_name, 'group']
        except KeyError:
            return ''
        return group_name