AttributeError: 'NoneType' object has no attribute 'split'

 I get the following error with the rest api

...flask-rest-api/app/__init__.py", line 35, in bucketlists
```
 access_token = auth_header.split(" ")[1]
access_token = auth_header.split(" ")[1]
AttributeError: 'NoneType' object has no attribute 'split'
```