sample.py

import tornado_mysql
from tornado import ioloop, gen

@gen.coroutine
def main():
    print("trying to connect to MySQL")
    conn = yield tornado_mysql.connect(host='127.0.0.1', user='root', db='test')
    cur = conn.cursor()
    yield cur.execute("CREATE TABLE tornado_test (a int)")
    query = "INSERT INTO tornado_test (a) values (42)"
    yield cur.execute(query) # this is getting executed!
    yield cur.close()
    yield conn.commit()
    yield conn.close_async() # tried conn.close() as well, Both throws an exception:
    print('end')

ioloop.IOLoop.current().run_sync(main)