Code in **Python**

***CANNOT USE**

Cannot use other built-in function besides len - specifically not max, min, slice

Cannot use slice notation in conjunction with the subscription operator

Cannot use the in operator of Python with lists (but you can use for..in loops!)

Cannot use the list classs + or == operators (you can still use + with int and str types, though!) nor built-in methods beyond append and pop

Note: You can use + and == for individual items and values, just not entire list objects.

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Part 1 . only_evens This is the first function you will write in utils.py. The other two functions will also be defined in this file.

Given a list of ints, only_evens should return a new list containing only the elements of the input list that were even. The only_evens function must not modify the list it is given a reference to as a parameter. Example usage:

>>> only_evens([1, 2, 3]) [2] >>> only_evens([1, 5, 3]) [] >>> only_evens([4, 4, 4]) [4, 4, 4] Continue by defining a skeleton function with the following signature:

- Name: only_evens - Arguments: A list of integers. - Returns: A list of integers, containing only the even elements of the input parameter.

Part 2. concat write a function named concat. Given two Lists of ints, concat should generate a new List that contains all of the elements of the first list followed by all of the elements of the second list. Your concat function may not mutate (modify) either of its list parameters.

Define your function with the following signature.

- Name: concat - Parameters: Two lists of ints. - Returns: A list containing all elements of the first list, followed by all elements of the second list. concat must NOT mutate (modify) either of the arguments passed to it.

PART 3. sub Write a function named sub. Given a list of ints, a start index, and an end index (not inclusive), sub should generate a List which is a subset of the given list, between the specified start index and the end index - 1. This function should not mutate its input list.

Example usage:

>>> a_list = [10, 20, 30, 40] >>> sub(a_list, 1, 3) [20, 30] Next, define a skeleton function with the following signature :

- Name: sub - Parameters: A list and two ints, where the first int serves as a start index and the second int serves as an end index (not inclusive). - Returns: A List which is a subset of the given list, between the specified start index and the end index - 1. If the start index is negative, start from the beginning of the list. If the end index is greater than the length of the list, end with the end of the list.

If the length of the list is 0, start is greater than or equal to the length of the list, or end is at most 0, return the empty list.