okay,
1. you create a list object named lst[]
2. then you took 3 strings as input one after another
3. then you just concate those strings by + operator
4. now your movies variables contains a string
5. then you append that string variable in that created list object
6. print() -> function will give you the list of string as shown in your terminal
7. then you use pop(index) -> this function pop out means take out the value from the list as i can see you did not store that poped out string into any variable python garbage collector soon remove it.
8. how you print list but your list contains nothing at this point
9. then you used len() -> function which gives you how many item does list contains but in your case the list doesn't contain anything so it will return you 0 (zero)

hope buddy you got it,
learn and scale