Slicing Python list of strings into individual characters

[Drone4four]

I’m trying to get slice a list of strings into individual characters ...but using slicing.

Here is my list:

first_list = ["apples", "bananas", "oranges",]

Here is the end result and what I am trying to achieve:

['a', 'p', 'p', 'l', 'e', 's', 'b', 'a', 'n', 'a', 'n', 'a', 's', 'o', 'r', 'a', 'n', 'g', 'e', 's']

I succeeded using a for loop:

for item in first_list:
   for character in item:
       second_list.append(character)
print(second_list)

That’s a basic for loop which I completely understand the syntax and logic.

But I am now trying to come up with an alternate solution this time using slicing. Here is my valiant attempt:

print(third_list.append(first_list[:][:]))

My interpreter prints ‘None’ with that code. I am not sure why. Could someone explain?

My humble lucid, cerebral explanation for that one-liner is: Python is printing the third_list variable which is a composition of each letter (appended together) contained in first_list. I’m obviously mistaken because the result is just None. Could someone please correct my explanation here?

I suppose a further and more important question that I have is this: Who among you could perform the same for loop operation that worked the first time but instead using two slices (as I have awkwardly attempted but failed to do)?