getArtifactNodeFromModifier(modifier) {
    let artifactNode;
    if (modifier instanceof SDK.Modifier && modifier.getIsFromArtifact()) {
      const sourceCard = modifier.getSourceCard();
      // search artifact nodes for matching artifact card
      for (let i = 0, il = this._artifactNodes.length; i < il; i++) {
        const existingArtifactNode = this._artifactNodes[i];
        if (existingArtifactNode.getSdkCard() === sourceCard) {
          artifactNode = existingArtifactNode;
          break;
        }
      }
    }
    return artifactNode;
  }
Returns an artifact node given a modifier, or null if this modifier is not linked to any existing artifact nodes.
@param {SDK.Modifier} modifier
@returns {ArtifactNode|null}