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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_headers(self, table_name, group_name):
 """ Return a list of all headers for a given group """

        # get all headers of a particular group
        df = self.dm[table_name]
        cond = df['group'] == group_name
        return df[cond].index