What language to learn to contribute to open source?

Working on this program in python 3.7: a year in the modern gregorian calendar consists of 365 days. in reality, the earth takes longer to rotate around the sun. to account for the difference in time, every 4 years, a leap year takes place. a leap year is when a year has 366 days: an extra day, february 29th. the requirements for a given year to be a leap year are: 1) the year must be divisible by 42) if the year is a century year (1700, 1800, the year must be evenly divisible by 400some example leap years are 1600, 1712, and 2016.write a program that takes in a year and determines whether that year is a leap year. ex: if the input is 1712, the output is: 1712 is a leap year. ex: if the input is 1913, the output is: 1913 is not a leap year. your program must define and call the function isleapyear(useryear). the function should return true if the input year is a leap year and false otherwise.

If an improvement creates no significant change in a product’s performance, then it is a(n) ? a0 design improvement. (there are no answer choices)

Write a program that keeps asking the user for new values to be added to a list until the user enters 'exit' ('exit' should not be added to the list). these values entered by the user are added to a list we call 'initial_list'. then write a function that takes this initial_list as input and returns another list with 3 copies of every value in the initial_list. finally, inside print out all of the values in the new list. for example: input: enter value to be added to list: a enter value to be added to list: b enter value to be added to list: c enter value to be added to list: exit output: a b c a b c a b c note how 'exit' is not added to the list. also, your program needs to be able to handle any variation of 'exit' such as 'exit', 'exit' etc. and treat them all as 'exit'.