'Delete a file from GridFS by ``"_id"``.
Deletes all data belonging to the file with ``"_id"``:
`file_id`.
.. warning:: Any processes/threads reading from the file while
this method is executing will likely see an invalid/corrupt
file. Care should be taken to avoid concurrent reads to a file
while it is being deleted.
.. note:: Deletes of non-existent files are considered successful
since the end result is the same: no file with that _id remains.
:Parameters:
- `file_id`: ``"_id"`` of the file to delete
.. versionchanged:: 3.1
``delete`` no longer ensures indexes.'

def delete(self, file_id):

    self.__files.delete_one({'_id': file_id})
    self.__chunks.delete_many({'files_id': file_id})
