When we read a file, we might want to grab the whole document in a single string, like .read() would return. But what if we wanted to store each line in a variable? We can use the .readlines() function to read a text file line by line instead of having the whole thing. Suppose we have a file:

keats_sonnet.txt

To one who has been long in city pent,
’Tis very sweet to look into the fair
And open face of heaven,—to breathe a prayer
Full in the smile of the blue firmament.

script.py

with open('keats_sonnet.txt') as keats_sonnet:
  for line in keats_sonnet.readlines():
    print(line)

The above script creates a temporary file object called keats_sonnet that points to the file keats_sonnet.txt. It then iterates over each line in the document and prints the entire file out.