def spawn(self):
        """Spawn mongocryptd.

        Note this method is thread safe; at most one mongocryptd will start
        successfully.
        """
        self._spawned = True
        args = [self.opts._mongocryptd_spawn_path or 'mongocryptd']
        args.extend(self.opts._mongocryptd_spawn_args)
        subprocess.Popen(args)
Spawn mongocryptd.

        Note this method is thread safe; at most one mongocryptd will start
        successfully.
        
stackoverflow/venv/lib/python3.6/site-packages/pymongo/encryption.py