Repro for openapi-generator issue

Listen.ts

/* tslint:disable */
/* eslint-disable */
/**
 * FastAPI
 * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
 *
 * The version of the OpenAPI document: 0.1.0
 * 
 *
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
 * https://openapi-generator.tech
 * Do not edit the class manually.
 */

import { exists, mapValues } from '../runtime';
/**
 * 
 * @export
 * @interface Listen
 */
export interface Listen {
    /**
     * 
     * @type {boolean | string}
     * @memberof Listen
     */
    classBot?: boolean | string;
}

export function ListenFromJSON(json: any): Listen {
    return ListenFromJSONTyped(json, false);
}

export function ListenFromJSONTyped(json: any, ignoreDiscriminator: boolean): Listen {
    if ((json === undefined) || (json === null)) {
        return json;
    }
    return {
        
        'classBot': !exists(json, 'class_bot') ? undefined : boolean | stringFromJSON(json['class_bot']),
    };
}

export function ListenToJSON(value?: Listen | null): any {
    if (value === undefined) {
        return undefined;
    }
    if (value === null) {
        return null;
    }
    return {
        
        'class_bot': boolean | stringToJSON(value.classBot),
    };
}

openapi.json

{
  "openapi": "3.0.2",
  "info": { "title": "FastAPI", "version": "0.1.0" },
  "paths": {
    "/current": {
      "get": {
        "summary": "Current Listeners",
        "operationId": "current_listeners_current_get",
        "responses": {
          "200": {
            "description": "Successful Response",
            "content": {
              "application/json": {
                "schema": {
                  "title": "Response Current Listeners Current Get",
                  "type": "array",
                  "items": { "$ref": "#/components/schemas/Listen" }
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "Listen": {
        "title": "Listen",
        "required": [
        ],
        "type": "object",
        "properties": {
          "class_bot": {
            "title": "Class Bot",
            "anyOf": [{ "type": "boolean" }, { "type": "string" }]
          }
        }
      }
    }
  }
}