def add_two(nums):
    new_nums = []

    for num in nums:
        new_nums += [num + 2]

    return new_nums

def add_two_to_first_two(nums):
    new_nums = []

    for num in nums[:2]:
        new_nums += [num +2]

    for num in nums[2:]:
        new_nums += [num]

    #new_nums = nums[:]
    #new_nums[0] += 2
    #new_nums[1] += 2
            
    return new_nums

def insert_seven_after_five(nums):
    new_nums = []

    for num in nums:
        new_nums += [num]
        if num == 5:
            new_nums += [7]

    return new_nums

def only_even(nums):
    new_nums = []

    for num in nums:
        if num % 2 == 0:
            new_nums += [num]

    return new_nums