23401

my_list = [74, 154, 74, 90, 946, 995, 745, 549, 649, 522, 397, 129, 741, 299, 230]
middle_of_list = len(my_list) // 2
print(my_list)
my_list_copy = my_list.copy()
my_list_copy.reverse()
my_list.extend(my_list)
print(my_list)
print(sorted(my_list))
my_list.append(max(my_list))
my_list.sort(reverse=True)
print(my_list)
my_list.insert(middle_of_list, sum(my_list))
print(my_list)
my_list.insert(0, min(my_list))
print(my_list)
for i in my_list:
    if i % 10 == 8:
        my_list.remove(i)
        break
print(my_list)
my_list.insert(0, max(my_list))
print(my_list)
for j in my_list:
    if j % 10 == 7:
        my_list.insert(3, j)
        break
print(my_list)