How to list all lines from a file?

Question

Python

I can't figure out how to list all lines from a file?
I found such a method, but it reads the file line by line, and I need to open the file, read its contents into a variable (about 200 lines) and close it, then work with this variable.
Since the process there will be long, and you will not have to keep the file open.

for x in open("DATA.txt", "r").readlines():    
    print(x)

Need to process each row in a for loop

Answer 1

with open("DATA.txt") as file:
  lines = file.read().splitlines()

for line in lines:
  print(line)