Sort List of Tuples by Date element

Question

I need the oldest people be first on the list, here is the example of the format i have to sort:

List =[ ('John', '12345', '1972-02-08'),
('Sara', '12345', '1977-07-01'),  
('Mario', '12345', '1971-06-13') ,   
('Lucas', '12345', '1967-04-27'),
('Kiara', '12345', '1973-02-15')]

Im new on python so i have some doubts on this. ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎

Answer 1

You can use sort(), sorted(), or datetime:

from datetime import datetime as dt

List = [
    ('John', '12345', '1972-02-08'),
    ('Sara', '12345', '1977-07-01'),
    ('Mario', '12345', '1971-06-13'),
    ('Lucas', '12345', '1967-04-27'),
    ('Kiara', '12345', '1973-02-15')
]

print(sorted(List, key=lambda x: dt.strptime(x[2], '%Y-%m-%d')))
print(sorted(List, key=lambda x: x[2]))

Prints

[('Lucas', '12345', '1967-04-27'), ('Mario', '12345', '1971-06-13'), ('John', '12345', '1972-02-08'), ('Kiara', '12345', '1973-02-15'), ('Sara', '12345', '1977-07-01')]
[('Lucas', '12345', '1967-04-27'), ('Mario', '12345', '1971-06-13'), ('John', '12345', '1972-02-08'), ('Kiara', '12345', '1973-02-15'), ('Sara', '12345', '1977-07-01')]

Comments

• Since the dates are in ISO format, you can just sort them as strings, you don't need to parse them. – Barmar