PyAthena - Invalid length for parameter RoleArn

Question

I am trying to use Python, PyAthena, and SQLAlchemy to connect to Athena.

When trying to define a SQLAlchemy cursor:

from pyathena import connect

cursor = connect(
    aws_access_key_id=aws_access_key, 
    aws_secret_access_key=aws_secret_key, 
    s3_staging_dir=s3_staging_dir,
    region_name=aws_region,
    schema_name=schema_name, 
    role_arn=aws_workgroup
).cursor()

I get this error:

ParamValidationError: Parameter validation failed:
Invalid length for parameter RoleArn, value: 14, valid min length: 20

The string for aws_workgroup, which is correct and I cannot change, is 14 characters long. I came across this issue in botocore from 2018, but it refers to aws-visualizer, and I don't know what that is or if I'm using it (or boto, for that matter).

If I remove role_arn from the cursor, that code will run, but then I get this permissions error when trying to execute a query:

DatabaseError: An error occurred (AccessDeniedException) when calling the StartQueryExecution operation: 
You are not authorized to perform: athena:StartQueryExecution on the resource. 
After your AWS administrator or you have updated your permissions, please try again.

I have verified the credentials in other applications, so it is not an issue with the credentials provided.

How do I fix the RoleArn error? Or is there another method to connect to Athena in Python that gets around this?