code: function appendModelPath (modelPath, id, internal) {
    const addedModelPath = getModelPath(id)
    if (internal) {
      if (modelPath === '') {
        return `properties._internal.${addedModelPath}`
      }
      return `${modelPath}.properties._internal.${addedModelPath}`
    }
    if (modelPath === '') {
      return addedModelPath
    }
    return `${modelPath}.${addedModelPath}`
  }
docs: Create a path to add within a model
  
  @param {String} modelPath Path to current place within the model
  @param {String} id Id specified in the cell
  @param {Boolean} internal True if we want to add an internal model
  @returns {String} Path to add within the model