I am trying to put my own custom DICOM dataset from google cloud API healthcare, I have already created both dataset and datastore then put folder with 20 instances by using bucket. In their guide it is written that I have to put the following snippet of code in order to extend datasource into google cloud API and make it active

extensionManager.addDataSource({
  namespace: '@ohif/extension-default.dataSourcesModule.dicomweb',
  sourceName: 'google',
  configuration: {
    friendlyName: 'dcmjs DICOMWeb Server',
    name: 'GCP',
    wadoUriRoot:
      'https://healthcare.googleapis.com/v1/projects/ohif-cloud-healthcare/locations/us-east4/datasets/ohif-qa-dataset/dicomStores/ohif-qa-2/dicomWeb',
    qidoRoot:
      'https://healthcare.googleapis.com/v1/projects/ohif-cloud-healthcare/locations/us-east4/datasets/ohif-qa-dataset/dicomStores/ohif-qa-2/dicomWeb',
    wadoRoot:
      'https://healthcare.googleapis.com/v1/projects/ohif-cloud-healthcare/locations/us-east4/datasets/ohif-qa-dataset/dicomStores/ohif-qa-2/dicomWeb',
    qidoSupportsIncludeField: true,
    imageRendering: 'wadors',
    thumbnailRendering: 'wadors',
    enableStudyLazyLoad: true,
    supportsFuzzyMatching: true,
    supportsWildcard: false,
    dicomUploadEnabled: true,
    omitQuotationForMultipartRequest: true,
  },
  {activate:true}
});

The problem is that I cant find a file where the changes above should be placed as the downloaded repository is huge for me and hard to navigate, I would have liked to know how to customize data source in more detailed steps.