testing an open file

[Larz60+]

you can get the mode (and much more) by using stats

for example (run from script path -- modify path as required --, probably better to use pathlib):
modified from example here: https://docs.python.org/3/library/os.html#os.scandir

import os

path = os.getcwd()
with os.scandir(path) as it:
    for entry in it:
        if not entry.name.startswith('.') and entry.is_file():
            stats = os.stat(path, follow_symlinks=False)
            print(stats)

see https://docs.python.org/3/library/stat.html on how to interpret the stat results.