Looking for an up to date example to query mysql

[buran]

I am not sure I fully understand your question, but json.dumps(rows) will create string and your function will return a dict. I think what you actually need is to make the return like this

return json.dumps({
    'statusCode':200,
    'headers': {'Access-Control-Allow-Origin': '*'},
    'body': rows
    })

full example

import json

def handler():
    # assume here it retrieve rows from db
    rows = [[""], ["Adelaide"], ["Alexandria"], ["Alice Springs"]]
    
    return json.dumps({
    'statusCode':200,
    'headers': {'Access-Control-Allow-Origin': '*'},
    'body': rows
    })
    
print(handler())

Output:
{"statusCode": 200, "headers": {"Access-Control-Allow-Origin": "*"}, "body": [[""], ["Adelaide"], ["Alexandria"], ["Alice Springs"]]}
>>>

as you can see it's a valid json
i.e. I think your function should return str that is valid json, not dict