def __enter__(self):
    self.process = subprocess.Popen([self.executable, '-stay_open', 'True',
        '-@', '-'], stdin=subprocess.PIPE, stdout=subprocess.PIPE)
return self

def __exit__(self, exc_type, exc_value, traceback):
    self.process.stdin.write('-stay_open\nFalse\n')
self.process.stdin.flush()

def execute(self, *args):
    pass
Вызвать exiftool из скрипта Python?