Mocking a model class using Pytest

Question

I have a class which I would like to mock. It is a simple model class. I would like this class object to be sent to another method. I would like to have different values for this class's attributes to test (want to create multiple objects and pass to get_api_response method) I want to know how can I mock the class object as json.

model.py

class Customer:
    id: int
    name: int
    address: str
    isRepeatedCustomer: bool
    def __init__(self) :
        self.id: None
        self.name: None
        self.address: None
        self.isRepeatedCustomer: false
        return

Service.py

def get_api_response(self, customerObj):
     if(customerObj.id is Not None):
        //API processing
        return api_response

I have used as follows:

with mock.patch('model.Customer') as MockCustomer:
    validResponse = json.dumps({"id":324,"name":"abc","address":"Grand Avenue", "isRepeatingCustomer":true})
    MockCustomer.return_value = validResponse

I am not sure if this is the right way to do this mocking. How can I pass this mocked object to test get_api_reponse method. How can I make validReponse as an argument so that I can send different json objects to test.