example6.py

# Example 5

def main():
    # Create a list that contains the names of Canadian provinces.
    provinces_list = [
        "Alberta", "Ontario", "Prince Edward Island", "Ontario",
        "Quebec", "Saskatchewan", "AB", "Nova Scotia", "Alberta",
        "Northwest Territories", "Saskatchewan", "Nunavut",
        "Nova Scotia", "Prince Edward Island", "Alberta",
        "Nova Scotia", "Prince Edward Island", "Saskatchewan",
        "Nova Scotia", "Newfoundland and Labrador", "Ontario",
        "Ontario", "Ontario", "British Columbia", "Ontario",
        "Nova Scotia", "Prince Edward Island", "Saskatchewan",
        "Newfoundland and Labrador", "Ontario", "Ontario",
        "Manitoba", "British Columbia", "Ontario", "Alberta",
        "Saskatchewan", "Ontario", "Manitoba", "Ontario",
        "New Brunswick", "Yukon", "British Columbia", "Yukon",
        "Newfoundland and Labrador", "Manitoba", "Ontario",
        "Yukon", "British Columbia", "Yukon", "Ontario", "AB",
        "Newfoundland and Labrador", "Nova Scotia", "Yukon",
        "Northwest Territories", "Nunavut", "Yukon", "Nunavut",
        "Ontario", "British Columbia", "AB", "Saskatchewan",
        "Prince Edward Island", "Saskatchewan",
        "Prince Edward Island", "Alberta", "Ontario", "Alberta",
        "Manitoba", "AB", "British Columbia", "Alberta"
    ]

    # As a debugging aid, print the entire list.
    print("Original list of provinces:")
    print(provinces_list)
    print()

    # Define a nested function that converts AB to Alberta.
    def alberta_from_ab(province_name):
        if province_name == "AB":
            province_name = "Alberta"
        return province_name

    # Replace all occurrences of "AB" with "Alberta" by
    # calling the map function and passing the ablerta_from_ab
    # function and provinces_list into the map function.
    new_list = list(map(alberta_from_ab, provinces_list))
    print("List of provinces after AB was changed to Alberta:")
    print(new_list)
    print()

    # Define a nested function that returns True if
    # province_name is Alberta and returns False otherwise.
    def is_alberta(province_name):
        return province_name == "Alberta"

    # Filter the new list to only those provinces that
    # are "Alberta" by calling the filter function and
    # passing the is_alberta function and new_list.
    filtered_list = list(filter(is_alberta, new_list))
    print("List filtered to Alberta only:")
    print(filtered_list)
    print()

    # Because all the elements in filtered_list are
    # "Alberta", we can count how many elements are
    # "Alberta" by simply calling the len function.
    count = len(filtered_list)

    print(f"Alberta occurs {count} times in the modified list.")


# Call main to start this program.
if __name__ == "__main__":
    main()