from pymongo import MongoClient
import gridfs

client = MongoClient('mongodb://localhost:27017/')
db = client.my_app
file_system = gridfs.GridFS(db)

_id = file_system.put(b"hello world")
print(_id)
print(str(_id))
print(file_system.get(_id).read())
print(file_system.get(str(_id)).read())

5e84dcec7ca83a32a5e09aa8
5e84dcec7ca83a32a5e09aa8
b'hello world'
Traceback (most recent call last):
 File "duck.py", line 12, in <module>
 print(file_system.get(str(_id)).read())
 File "/usr/local/lib/python3.7/dist-packages/gridfs/__init__.py", line 153, in get
 gout._ensure_file()
 File "/usr/local/lib/python3.7/dist-packages/gridfs/grid_file.py", line 490, in _ensure_file
 (self.__files, self.__file_id))
gridfs.errors.NoFile: no file in gridfs collection Collection(Database(MongoClient(host=['localhost:27017'], document_class=dict, tz_aware=False, connect=True), 'my_app'), 'fs.files') with _id '5e84dcec7ca83a32a5e09aa8'