code: function scoreCandidate (node, contentScore, candidates) {
    let score
    if (typeof node.data('readabilityScore') === 'undefined') {
      score = initializeNode(node)
      candidates.push(node)
    } else {
      score = node.data('readabilityScore') || 0
    }
    node.data('readabilityScore', score + contentScore)
  }
docs: Give a score to each node based on the Content.
  @param node
  @param contentScore
  @param candidates