function toFormData(obj, formData, options) {
  if (!utils$1.isObject(obj)) {
    throw new TypeError('target must be an object');
  }

  // eslint-disable-next-line no-param-reassign
  formData = formData || new (FormData)();

  // eslint-disable-next-line no-param-reassign
  options = utils$1.toFlatObject(options, {
    metaTokens: true,
    dots: false,
    indexes: false
  }, false, function defined(option, source) {
    // eslint-disable-next-line no-eq-null,eqeqeq
    return !utils$1.isUndefined(source[option]);
  });

  const metaTokens = options.metaTokens;
  // eslint-disable-next-line no-use-before-define
  const visitor = options.visitor || defaultVisitor;
  const dots = options.dots;
  const indexes = options.indexes;
  const _Blob = options.Blob || typeof Blob !== 'undefined' && Blob;
  const useBlob = _Blob && utils$1.isSpecCompliantForm(formData);

  if (!utils$1.isFunction(visitor)) {
    throw new TypeError('visitor must be a function');
  }

  function convertValue(value) {
    if (value === null) return '';

    if (utils$1.isDate(value)) {
      return value.toISOString();
    }

    if (!useBlob && utils$1.isBlob(value)) {
      throw new AxiosError('Blob is not supported. Use a Buffer instead.');
    }

    if (utils$1.isArrayBuffer(value) || utils$1.isTypedArray(value)) {
      return useBlob && typeof Blob === 'function' ? new Blob([value]) : Buffer.from(value);
    }

    return value;
  }

  /**
   * Default visitor.
   *
   * @param {*} value
   * @param {String|Number} key
   * @param {Array<String|Number>} path
   * @this {FormData}
   *
   * @returns {boolean} return true to visit the each prop of the value recursively
   */
  function defaultVisitor(value, key, path) {
    let arr = value;

    if (value && !path && typeof value === 'object') {
      if (utils$1.endsWith(key, '{}')) {
        // eslint-disable-next-line no-param-reassign
        key = metaTokens ? key : key.slice(0, -2);
        // eslint-disable-next-line no-param-reassign
        value = JSON.stringify(value);
      } else if (
        (utils$1.isArray(value) && isFlatArray(value)) ||
        ((utils$1.isFileList(value) || utils$1.endsWith(key, '[]')) && (arr = utils$1.toArray(value))
        )) {
        // eslint-disable-next-line no-param-reassign
        key = removeBrackets(key);

        arr.forEach(function each(el, index) {
          !(utils$1.isUndefined(el) || el === null) && formData.append(
            // eslint-disable-next-line no-nested-ternary
            indexes === true ? renderKey([key], index, dots) : (indexes === null ? key : key + '[]'),
            convertValue(el)
          );
        });
        return false;
      }
    }

    if (isVisitable(value)) {
      return true;
    }

    formData.append(renderKey(path, key, dots), convertValue(value));

    return false;
  }

  const stack = [];

  const exposedHelpers = Object.assign(predicates, {
    defaultVisitor,
    convertValue,
    isVisitable
  });

  function build(value, path) {
    if (utils$1.isUndefined(value)) return;

    if (stack.indexOf(value) !== -1) {
      throw Error('Circular reference detected in ' + path.join('.'));
    }

    stack.push(value);

    utils$1.forEach(value, function each(el, key) {
      const result = !(utils$1.isUndefined(el) || el === null) && visitor.call(
        formData, el, utils$1.isString(key) ? key.trim() : key, path, exposedHelpers
      );

      if (result === true) {
        build(el, path ? path.concat(key) : [key]);
      }
    });

    stack.pop();
  }

  if (!utils$1.isObject(obj)) {
    throw new TypeError('data must be an object');
  }

  build(obj);

  return formData;
}
It converts an object into a FormData object

@param {Object<any, any>} obj - The object to convert to form data.
@param {string} formData - The FormData object to append to.
@param {Object<string, any>} options

@returns