[Python] Python writing to file from multiple separate Python processes, do I have to lock...

I have a Python script that is running in a number of different Kubernetes pods at all times (minimum 1, max ~100 at the same time).

These processes are largely independent of each other, except that at one point, they have to write to the same file (last_appended.txt) in the following fashion:

with open(filepath, 'w') as file:
file.write(str(int(time.timestamp())))


I am wondering if I have to do any sort of locking on this file or if this is such a minimal operation that this is not necessary?

If I would want to lock the file, I have found the following code to enable this:

with open(filepath, 'w') as file:
fcntl.flock(file, fcntl.LOCK_EX)
file.write(str(int(time.timestamp())))
fcntl.flock(file, fcntl.LOCK_UN)


However, I wonder if this is enough to let my processes run smoothly, or that I maybe have to write some sort of try/except loop when a lock is encountered by a process.

Summarising, my question is two-fold:

1. Would I have to lock the file at all, or is this such a small operation that it can be done by multiple processes without crashing, and
2. If no, would my solution to the multiple processes writing to the file be sufficient?

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