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Python json to object from model

I know this looks like Frequency Ask Question mainly this question: How to convert JSON data into a Python object?

I will mention most voted answer:

import json
from types import SimpleNamespace

data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'

# Parse JSON into an object with attributes corresponding to dict keys.
x = json.loads(data, object_hook=lambda d: SimpleNamespace(**d))
print(x.name, x.hometown.name, x.hometown.id)

Based on that answer, x is object. But it’s not object from model. I mean model that created with class. For example:

import json
from types import SimpleNamespace

class Hometown:
  def __init__(self, name : str, id : int):
    self.name = name
    self.id = id


class Person:  # this is a model class
  def __init__(self, name: str, hometown: Hometown):
    self.name = name
    self.hometown = hometown


data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
x = Person(what should I fill here?) # I expect this will automatically fill properties from constructor based on json data 
print(type(x.hometown)) # will return Hometown class

I’m asking this is simply because my autocompletion doesn’t work in my code editor if I don’t create model class. For example if I type dot after object, it will not show properties name.

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Answer

This is how you can achieve that.

class Person:  # this is a model class
    def __init__(self, name: str, hometown: dict):
        self.name = name
        self.hometown = Hometown(**hometown)


x = Person(**json.loads(data))
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