import json
schema = json.loads(
    """{
  "$schema": "http://json-schema.org/schema#",
  "description": "Schemas for heading: either a number within [0, 360) or null.",
  "title": "Tester for number-or-null schema",
  "properties": {
    "heading": {
      "type": ["number", "null"],
      "exclusiveMinimum": false,
      "exclusiveMaximum": true,
      "minimum": 0,
      "maximum": 360
    }
  }
}"""
    )
Схема JSON: проверка числового или нулевого значения