I'm getting the error "The role defined for the function cannot be assumed by Lambda" when I'm trying to create a lambda function with create-function command.

aws lambda create-function
  --region us-west-2
  --function-name HelloPython
  --zip-file fileb://hello_python.zip
  --role arn:aws:iam::my-acc-account-id:role/default
  --handler hello_python.my_handler
  --runtime python2.7
  --timeout 15
  --memory-size 512
It could be that the Lambda is missing an execution role. Or this role has been deleted.
In console you can see the status at Lambda > Functions > YourFunction > Permissions. Even an IAM empty role with no policies is enough to make it work.
The role defined for the function cannot be assumed by Lambda