How to use the prosemirror-transform.Step function in prosemirror-transform

var steps = diffs.map(function (jIndex) {
    return _prosemirrorTransform.Step.fromJSON(schema, jIndex);
  });
  var _iteratorNormalCompletion = true;

var steps = [diff].map(function (jIndex) {
							return _prosemirrorTransform.Step.fromJSON(_setup.schema, jIndex);
						});
						var clientIds = [diff].map(function (jIndex) {

var steps = [diff].map(function (jIndex) {
				return _prosemirrorTransform.Step.fromJSON(_setup.schema, jIndex);
			});
			var clientIds = [diff].map(function (jIndex) {

key: 'toJSON',
    value: function toJSON() {
      return {
        stepType: this.stepType,
        key: this.key,
        value: this.value
      };
    }
  }], [{
    key: 'fromJSON',
    value: function fromJSON(json) {
      return new SetDocAttrStep(json.key, json.value, json.stepType);
    }
  }]);
  return SetDocAttrStep;
}(_prosemirrorTransform.Step);

exports.default = SetDocAttrStep;

var _firebase = require('firebase');

var _firebase2 = _interopRequireDefault(_firebase);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }

var _require = require('prosemirror-state'),
    Selection = _require.Selection;

var _require2 = require('prosemirror-model'),
    Node = _require2.Node;

var _require3 = require('prosemirror-transform'),
    Step = _require3.Step,
    Mapping = _require3.Mapping;

var _require4 = require('prosemirror-collab'),
    sendableSteps = _require4.sendableSteps,
    receiveTransaction = _require4.receiveTransaction;

var _require5 = require('prosemirror-compress'),
    compressStepsLossy = _require5.compressStepsLossy,
    compressStateJSON = _require5.compressStateJSON,
    uncompressStateJSON = _require5.uncompressStateJSON,
    compressSelectionJSON = _require5.compressSelectionJSON,
    uncompressSelectionJSON = _require5.uncompressSelectionJSON,
    compressStepJSON = _require5.compressStepJSON,
    uncompressStepJSON = _require5.uncompressStepJSON;

var TIMESTAMP = { '.sv': 'timestamp' };

var _steps = [diff].map(function (jIndex) {
								return _prosemirrorTransform.Step.fromJSON(_setup.schema, jIndex);
							});
							var _clientIds = [diff].map(function (jIndex) {