How to use the cloudinary-core.Util.defaults function in cloudinary-core

render() {
    let {publicId, poster, sourceTypes, fallback, sourceTransformation: sourceTransformations, innerRef, ...options} = Object.assign({},
      this.getContext(),
      this.props);
    sourceTransformations = sourceTransformations || {};
    sourceTypes = sourceTypes || Cloudinary.DEFAULT_VIDEO_PARAMS.source_types;
    options = CloudinaryComponent.normalizeOptions(options, {});
    let cld = Cloudinary.new(Util.withSnakeCaseKeys(options));
    let sources = [];
    let tagAttributes = Transformation.new(options).toHtmlAttributes();
    let childTransformations = this.getTransformation(options);
    if (Util.isPlainObject(poster)) {
      let defaults = poster.publicId !== undefined && poster.publicId !== null ? Cloudinary.DEFAULT_IMAGE_PARAMS : DEFAULT_POSTER_OPTIONS;
      poster = cld.url(poster.publicId || publicId, Util.defaults({}, Util.withSnakeCaseKeys(poster), defaults));
    }
    if (!Util.isEmpty(poster)) {
      tagAttributes.poster = poster;
    }
    if (!Util.isEmpty(this.state.poster)) {
      tagAttributes.poster = this.state.poster;
    }

    if (Util.isArray(sourceTypes)) {
      sources = sourceTypes.map(srcType => {
          let sourceTransformation = sourceTransformations[srcType] || {};
          let src = cld.url(publicId, Util.defaults({}, sourceTransformation, childTransformations, {resource_type: 'video', format: srcType}));
          let mimeType = 'video/' + (srcType === 'ogv' ? 'ogg' : srcType);
          return <source type="{mimeType}/" src="{src}">;
        }
      );

sources = sourceTypes.map(srcType => {
          let sourceTransformation = sourceTransformations[srcType] || {};
          let src = cld.url(publicId, Util.defaults({}, sourceTransformation, childTransformations, {resource_type: 'video', format: srcType}));
          let mimeType = 'video/' + (srcType === 'ogv' ? 'ogg' : srcType);
          return <source type="{mimeType}/" src="{src}">;
        }
      );

}
    if (!Util.isEmpty(this.state.poster)) {
      tagAttributes.poster = this.state.poster;
    }

    if (Util.isArray(sourceTypes)) {
      sources = sourceTypes.map(srcType => {
          let sourceTransformation = sourceTransformations[srcType] || {};
          let src = cld.url(publicId, Util.defaults({}, sourceTransformation, childTransformations, {resource_type: 'video', format: srcType}));
          let mimeType = 'video/' + (srcType === 'ogv' ? 'ogg' : srcType);
          return <source type="{mimeType}/" src="{src}">;
        }
      );
    } else {
      let sourceTransformation = sourceTransformations[sourceTypes] || {};
      tagAttributes.src = cld.url(publicId, Util.defaults({}, sourceTransformation, childTransformations, {resource_type: 'video', format: sourceTypes}));
    }

    return (
      <video>
        {sources}
        {fallback}
        {this.props.children}
      </video>
    );
  }
}