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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 group_values(self, group_name):
 """Return all distinct group values for given group."""

        group_index = self.groups.index(group_name)
        values = []
        for key in self.data_keys:
            if key[group_index] not in values:
                values.append(key[group_index])
        return values