# You are given the current stock prices. You have to find out which stocks cost more.
#
# Input:
# The dictionary where the market identifier code is a key and the value is a stock price.
#
# Output:
# A string and the market identifier code.
#
# Example:
# best_stock({
#     'CAC': 10.0,
#     'ATX': 390.2,
#     'WIG': 1.2
# }) == 'ATX'
# best_stock({
#     'CAC': 91.1,
#     'ATX': 1.01,
#     'TASI': 120.9
# }) == 'TASI'
# Preconditions:
# All the prices are unique.

def best_stock(data: dict) -> str:
	key_list = list(data.keys())
	value_list = list(data.values())
	max_value = max(data.values())
	value_index = value_list.index(max_value)
	return key_list[value_index]

if __name__ == '__main__':
	print("Example:")
	print(best_stock({
		'CAC': 10.0,
		'ATX': 390.2,
		'WIG': 1.2
	}))

	# These "asserts" are used for self-checking and not for an auto-testing
	assert best_stock({
		'CAC': 10.0,
		'ATX': 390.2,
		'WIG': 1.2
	}) == 'ATX', "First"
	assert best_stock({
		'CAC': 91.1,
		'ATX': 1.01,
		'TASI': 120.9
	}) == 'TASI', "Second"
	print("Coding complete? Click 'Check' to earn cool rewards!")