code: def atomic_write_file(path, content):
    
    # Write to a randomly tmp file
    tmp_file = get_tmp_filename()
    with open(tmp_file, 'w') as f:
      f.write(content)
      # make sure that all data is on disk
      f.flush()
      os.fsync(f.fileno())
  
    # Rename the tmp file
    os.rename(tmp_file, path)
docs: file.write(...) is not atomic.
    We write to a tmp file and then rename to target path since rename is atomic.
    We do this to avoid the content of file is dirty read/partially read by others.