How to use the cornerstone-tools.init function in cornerstone-tools

import dicomParser from 'dicom-parser';
import cornerstone from 'cornerstone-core';
import cornerstoneWADOImageLoader from 'cornerstone-wado-image-loader';
import cornerstoneMath from 'cornerstone-math';
import cornerstoneTools from 'cornerstone-tools';
import Hammer from 'hammerjs';

cornerstoneTools.external.cornerstone = cornerstone;
cornerstoneTools.external.Hammer = Hammer;
cornerstoneTools.external.cornerstoneMath = cornerstoneMath;
cornerstoneTools.init();

// Set the tool font and font size
// context.font = "[style] [variant] [weight] [size]/[line height] [font family]";
const fontFamily =
  'Work Sans, Roboto, OpenSans, HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif';
cornerstoneTools.textStyle.setFont(`16px ${fontFamily}`);

// Set the tool width
cornerstoneTools.toolStyle.setToolWidth(2);
// Set color for inactive tools
cornerstoneTools.toolColors.setToolColor('rgb(255, 255, 0)');

// Set color for active tools
cornerstoneTools.toolColors.setActiveColor('rgb(0, 255, 0)');

cornerstoneTools.store.state.touchProximity = 40;

export default function(configuration = {}) {
  // For debugging
  window.cornerstoneTools = cornerstoneTools;

  cornerstoneTools.external.cornerstone = cornerstone;
  cornerstoneTools.external.Hammer = Hammer;
  cornerstoneTools.external.cornerstoneMath = cornerstoneMath;
  cornerstoneTools.init(configuration);

  // Set the tool font and font size
  // context.font = "[style] [variant] [weight] [size]/[line height] [font family]";
  const fontFamily =
    'Roboto, OpenSans, HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif';
  cornerstoneTools.textStyle.setFont(`16px ${fontFamily}`);

  // Tool styles/colors
  cornerstoneTools.toolStyle.setToolWidth(2);
  cornerstoneTools.toolColors.setToolColor('rgb(255, 255, 0)');
  cornerstoneTools.toolColors.setActiveColor('rgb(0, 255, 0)');

  cornerstoneTools.store.state.touchProximity = 40;
}

import dicomParser from 'dicom-parser';
import cornerstone from 'cornerstone-core';
import cornerstoneMath from 'cornerstone-math';
import cornerstoneWADOImageLoader from 'cornerstone-wado-image-loader';
import cornerstoneTools from 'cornerstone-tools';
import Hammer from 'hammerjs';

cornerstoneTools.external.cornerstone = cornerstone;
cornerstoneTools.external.Hammer = Hammer;
cornerstoneTools.external.cornerstoneMath = cornerstoneMath;

cornerstoneTools.init();

// Set the tool font and font size
// context.font = "[style] [variant] [weight] [size]/[line height] [font family]";
const fontFamily =
  'Work Sans, Roboto, OpenSans, HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif';
cornerstoneTools.textStyle.setFont(`16px ${fontFamily}`);

// Set the tool width
cornerstoneTools.toolStyle.setToolWidth(2);

// Set color for inactive tools
cornerstoneTools.toolColors.setToolColor('rgb(255, 255, 0)');

// Set color for active tools
cornerstoneTools.toolColors.setActiveColor('rgb(0, 255, 0)');

export default function initCornerstone() {
  // Cornertone Tools
  cornerstoneTools.external.cornerstone = cornerstone;
  cornerstoneTools.external.Hammer = Hammer;
  cornerstoneTools.external.cornerstoneMath = cornerstoneMath;

  //
  cornerstoneTools.init();

  // Preferences
  const fontFamily =
    'Work Sans, Roboto, OpenSans, HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif';
  cornerstoneTools.textStyle.setFont(`16px ${fontFamily}`);
  cornerstoneTools.toolStyle.setToolWidth(2);
  cornerstoneTools.toolColors.setToolColor('rgb(255, 255, 0)');
  cornerstoneTools.toolColors.setActiveColor('rgb(0, 255, 0)');

  cornerstoneTools.store.state.touchProximity = 40;

  // IMAGE LOADER
  cornerstoneWADOImageLoader.external.cornerstone = cornerstone;
  cornerstoneWADOImageLoader.external.dicomParser = dicomParser;
  cornerstoneWADOImageLoader.webWorkerManager.initialize({
    maxWebWorkers: navigator.hardwareConcurrency || 1,

export default function(configuration = {}) {
  // For debugging
  window.cornerstoneTools = cornerstoneTools;

  cornerstoneTools.external.cornerstone = cornerstone;
  cornerstoneTools.external.Hammer = Hammer;
  cornerstoneTools.external.cornerstoneMath = cornerstoneMath;
  cornerstoneTools.init(configuration);

  // Set the tool font and font size
  // context.font = "[style] [variant] [weight] [size]/[line height] [font family]";
  const fontFamily =
    'Roboto, OpenSans, HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif';
  cornerstoneTools.textStyle.setFont(`16px ${fontFamily}`);

  // Tool styles/colors
  cornerstoneTools.toolStyle.setToolWidth(2);
  cornerstoneTools.toolColors.setToolColor('rgb(255, 255, 0)');
  cornerstoneTools.toolColors.setActiveColor('rgb(0, 255, 0)');

  cornerstoneTools.store.state.touchProximity = 40;
}