Insert document in MongoDB using pymongo

I'm using Python for the first time to run a crawler. I've got the crawler to work and now I want to save the results in my MongoDB using pymongo,but for some reason I get this error: "NameError: name 'city' is not defined". If I wrap city in quotes,it works as expected,but I want to save it as it is. Anyone has done something similar or know what the solution is?

def gotHolidays(self, response):
        cityName = response.meta['name']
        feriado = []
        facult = []
        for selector in response.css("span.one"):
            feriado.append(selector.css("::text").extract())

        for selector in response.css("span.two"):
            facult.append(selector.css("::text").extract())

        city = {
            'city': cityName,
            'holidays':{
                'facult': facult,
                'feriado': feriado                
            }
        }
        print(json.dumps(city))

    from pymongo import MongoClient
    client = MongoClient()
    client = MongoClient ('localhost', 27017)
    db = client['myBank']
    myCollection = db.myCollection
    myCollection_data = {
        'cities': city
    }
    result = myCollection.insert_one (myCollection_data)

Copyright Notice：Content Author:「Bruce Espeschit」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/51442558/insert-document-in-mongodb-using-pymongo