问具有完全S3访问权限的IAM用户无法下载文件

EN

import os
import boto3
from dotenv import load_dotenv

# load environment variables
load_dotenv()

boto_session = boto3.session.Session(aws_access_key_id=os.getenv('AWS_ACCESS_ID'), aws_secret_access_key=os.getenv('AWS_ACCESS_KEY'), region_name=os.getenv('AWS_REGION'))
s3 = boto3.client('s3')

with open('test.txt', 'wb') as f:
    s3.download_fileobj('dev-tom', 'readme.txt', f)

Traceback (most recent call last):
  File "/.../lib/python3.7/site-packages/boto3/s3/inject.py", line 678, in download_fileobj
    return future.result()
  File "/.../lib/python3.7/site-packages/s3transfer/futures.py", line 106, in result
    return self._coordinator.result()
  File "/.../lib/python3.7/site-packages/s3transfer/futures.py", line 265, in result
    raise self._exception
  File "/.../lib/python3.7/site-packages/s3transfer/tasks.py", line 255, in _main
    self._submit(transfer_future=transfer_future, **kwargs)
  File "/.../lib/python3.7/site-packages/s3transfer/download.py", line 343, in _submit
    **transfer_future.meta.call_args.extra_args
  File "/.../lib/python3.7/site-packages/botocore/client.py", line 357, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "/.../lib/python3.7/site-packages/botocore/client.py", line 676, in _make_api_call
    raise error_class(parsed_response, operation_name)
botocore.exceptions.ClientError: An error occurred (403) when calling the HeadObject operation: Forbidden