How can I check if there is a Specific Word in a fileline?

Question

How can i fix my problem? I want to check if there is a specific word in a Textfile line and then run some code. Can someone please help me? Thanks alot.

    if key == Key.left:
        mouse.move(901, 350, absolute=True, duration=0.02)
        time.sleep(0.0001)
        mouse.click("left")
        time.sleep(0.0001)
        f = open('Get Position.txt', 'a+')
        f.write('LEFT \n')

    if key == Key.enter:
        file = open('Get Position.txt', 'r')
        file.close() 

with open('Get Position.txt') as file:                            
            contents = file.read()
            search_word = linecache.getline('Get Position.txt', 1)
            if search_word in contents == 'LEFT \n':
                print('LEFT WAS PRESSED')
                mouse.move(901, 350, absolute=True, duration=0.02)
                time.sleep(0.0001)
                mouse.click("left")