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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_line(self, data):
 """Get the next group-style key's line. :param data: the data to proceed :returns: the line number """

        idx = -1
        for key in self.groups:
            i = self.get_group_key_line(data, key)
            if (i < idx and i != -1) or idx == -1:
                idx = i
        return idx