Python sqlite code prtg

Hello,

What is the problem with following code?

import sqlite3
import json


def sl():
    conn = sqlite3.connect('cidb.db')
    cur = conn.cursor()
    cur.execute("SELECT cisdb FROM sw1;")
    one_result = cur.fetchone()
    st = int(one_result[0])
    return st
cis = sl()

channel = {}
channel["prtg"] = {"result":[{"channel" : "Status","value" : cis }]}
print(json.dumps(channel))

XML: Structural error in xml file, 1 open items. -- JSON: The returned JSON does not match the expected structure (Invalid JSON.). (code: PE231)

json prtg python sensor