So far the closest thing I've been able to find is warlock, which advertises this workflow:

Build your schema

>>> schema = {
    'name': 'Country',
    'properties': {
        'name': {'type': 'string'},
        'abbreviation': {'type': 'string'},
    },
    'additionalProperties': False,
}

Create a model

>>> import warlock
>>> Country = warlock.model_factory(schema)

Create an object using your model

>>> sweden = Country(name='Sweden', abbreviation='SE')

However, it's not quite that easy. The objects that Warlock produces lack much in the way of introspectible goodies. And if it supports nested dicts at initialization, I was unable to figure out how to make them work.

To give a little background, the problem that I was working on was how to take Chrome's JSONSchema API and produce a tree of request generators and response handlers. Warlock doesn't seem too far off the mark, the only downside is that meta-classes in Python can't really be turned into 'code'.

Other useful modules to look for:

• jsonschema - (which Warlock is built on top of)
• valideer - similar to jsonschema but with a worse name.
• bunch - An interesting structure builder thats half-way between a dotdict and construct

If you end up finding a good one-stop solution for this please follow up your question - I'd love to find one. I poured through github, pypi, googlecode, sourceforge, etc.. And just couldn't find anything really sexy.

For lack of any pre-made solutions, I'll probably cobble together something with Warlock myself. So if I beat you to it, I'll update my answer. :p

Pydantic can help you achieve this:

Example from the Pydantic documentation

from enum import Enum
from pydantic import BaseModel, Field


class FooBar(BaseModel):
    count: int
    size: float = None


class Gender(str, Enum):
    male = 'male'
    female = 'female'
    other = 'other'
    not_given = 'not_given'


class MainModel(BaseModel):
    """
    This is the description of the main model
    """

    foo_bar: FooBar = Field(...)
    gender: Gender = Field(None, alias='Gender')
    snap: int = Field(
        42,
        title='The Snap',
        description='this is the value of snap',
        gt=30,
        lt=50,
    )

    class Config:
        title = 'Main'


# this is equivalent to json.dumps(MainModel.schema(), indent=2):
print(MainModel.schema_json(indent=2))

Output:

# this is equivalent to json.dumps(MainModel.schema(), indent=2):
print(MainModel.schema_json(indent=2))

{
  "title": "Main",
  "description": "This is the description of the main model",
  "type": "object",
  "properties": {
    "foo_bar": {
      "$ref": "#/definitions/FooBar"
    },
    "Gender": {
      "$ref": "#/definitions/Gender"
    },
    "snap": {
      "title": "The Snap",
      "description": "this is the value of snap",
      "default": 42,
      "exclusiveMinimum": 30,
      "exclusiveMaximum": 50,
      "type": "integer"
    }
  },
  "required": [
    "foo_bar"
  ],
  "definitions": {
    "FooBar": {
      "title": "FooBar",
      "type": "object",
      "properties": {
        "count": {
          "title": "Count",
          "type": "integer"
        },
        "size": {
          "title": "Size",
          "type": "number"
        }
      },
      "required": [
        "count"
      ]
    },
    "Gender": {
      "title": "Gender",
      "description": "An enumeration.",
      "enum": [
        "male",
        "female",
        "other",
        "not_given"
      ],
      "type": "string"
    }
  }
}