How to let the user input as many lines of input as they want until they input the "stop" word in Python?

How to let the user input as many lines of input as they want until they
input the "stop" word in Python?

Say that I'm asking the user to input lines from a book or whatever. I
don't know how many lines they will decide to input though. How would you
let them input as many lines as they want until they input a secret word,
"blueblue" for example. That's the code i've got so far.
while (blueblue == false):
line1 = input()
Help would be much appreciated.