def get_age_bracket(school_type):
	"""Return the age structure for different school types."""
	age_brackets = {
		'primary':[6, 7, 8, 9],
		'primary_dc':[6, 7, 8, 9],
		'lower_secondary':[10, 11, 12, 13],
		'lower_secondary_dc':[10, 11, 12, 13],
		'upper_secondary':[14, 15, 16, 17],
		'secondary':[10, 11, 12, 13, 14, 15, 16, 17],
		'secondary_dc':[10, 11, 12, 13, 14, 15, 16, 17]
	}
	return age_brackets[school_type]