String comparisons from array and file?

Question

Python

I need to output all non-matching lines from the file

, here is the code, but I don’t understand what the error is

a = ['1','2'] 
file = open('test.txt')
for line in file:
  if line not in a:
    print(line)

file lines like
1
2
3
4
5
need to get 3,4,5

Answer 1

It seems to me that you have not read the data from the file, after opening it, you need to read the data.
And then compare them with the list.

file = open('test.txt')
data = file.read()