Python problem

The population of some of the countries is stored in a list of tuples called population_data. Each tuple contains three elements. The first element of each tuple is the year, stored as a string, the second element is the name of the country, stored as a string, and the third element is the population, stored as an integer. Write a function highest_population(populatian_data, year) which returns the country with the highest population in the given year (out of the information available in the given data set). Your function should return None if no records are available forthat year. See the examples given below. Note: Your function should work with any database (population_data) given.