What does .flush do? How can I change this to write to the file?

[Pedroski55]

Looking at using yield, I have this simulated log file: logsim.py

logsim.py has 2 very long lists, ips and docs

ips like this: ips = ['129.194.8.73', '198.37.27.153', '217.127.12.71', ...
docs like this: docs = ['"GET /ply/ply-2.0.tar.gz HTTP/1.0" 304 -',
'"GET /python/tutorial/beazley_advanced_python/Slides/SLIDE066.HTM HTTP/1.0" 200 1538', ....

The tutorial is here.

logsim.py code, apart from the lists ips and docs:

import time, random
# a fake log programme

f = open("/home/pedro/temp/access-log.log","w")

while True:
    time.sleep(random.random())
    n = random.randint(0,len(ips)-1)
    m = random.randint(0,len(docs)-1)
    t = time.time()
    date = time.strftime("[%d/%b/%Y:%H:%M:%S -0600]",time.localtime(t))
    #print(f,"%s - - %s %s" % (ips[n],date,docs[m]))
    print(f'{f} {ips[n]},{date},{docs[m]}')      
    f.flush()

For the tutorial it says, leave this running in the background, so I run it in bash.
But nothing is written to /home/pedro/temp/access-log.log when I run this in bash

Should I change f.flush() for f.write(ips[n] + ',' + date + ',' + docs[m])

Often, the file does not change until f.close() is called, but I can't do that, because logsim.py is still writing to f!

How to get the data actually written to /home/pedro/temp/access-log.log without closing the file?
How to dynamically update the file, without closing it?