Provide a helper to fully resolve $refs in a schema

首先检查被引用仓库现有的 API，以及此 issue 中的示例 schema。完整的结果应提供一种遍历 schema 的方式，将内部 $refs inline，同时避免因自引用而导致的无限展开。

I want to generate some documentation/description (probably some input forms) from a json schema that contains $refs. Is there a way in jsonschema to retrieve a json schema with $refs resolved and inlined, so I can iterate through the schema?

So from a schema like this:

{
  "definitions": {
    "some_object": {
      "type": "object",
      "title": "My definition",
      "description": "Some description",
      "properties": {
        "name": {
          "type": "string"
        },
        "value": {
          "type": "number"
        }
      }
    }
  },
  "properties": {
    "list_of_objects": {
      "type": "array",
      "title": "Some stuff",
      "description": "List of stuff",
      "items": {"$ref": "#/definitions/some_object"}
    }
  }
}

I want to have this structure in my Python object (notice that the {$ref:...} section is replaced by the actual definition):

{
  "definitions": {
    "some_object": {
      "type": "object",
      "title": "My definition",
      "description": "Some description",
      "properties": {
        "name": {
          "type": "string"
        },
        "value": {
          "type": "number"
        }
      }
    }
  },
  "properties": {
    "list_of_objects": {
      "type": "array",
      "title": "Some stuff",
      "description": "List of stuff",
      "items": {
        "type": "object",
        "title": "My definition",
        "description": "Some description",
        "properties": {
          "name": {
            "type": "string"
          },
          "value": {
            "type": "number"
          }
        }
      }
    }
  }
}

I am aware that with self-referencing schemas this will lead to an infinite structure, but hopefully this is feasible with reasonable limitations (eg. excluding self-refs).