code: async function parseUrlsOption (state, urls) {
    if (!urls || urls.length === 0) {
      // get URLs for all sections across all pages
      const pages = await getDocPages(state)
      return (await pages.reduce(toSectionUrls.bind(null, state), [])).map(normalizeUrl)
    }
  
    const normalizedUrls = urls.map(normalizeUrl)
    const invalidUrls = normalizedUrls.filter(isntV3DocumentationUrl)
    if (invalidUrls.length) {
      throw new Error(`Invalid URLs: ${invalidUrls.join(', ')}`)
    }
  
    const pageUrls = normalizedUrls.filter(isPageUrl)
  
    const sectionUrls = normalizedUrls.filter(isSectionUrl)
    return _.uniq((await pageUrls.reduce(toSectionUrls.bind(null, state), [])).concat(sectionUrls))
  }
docs: returns all section URLs from all documentation pages by default
  If URLs are passed than the page URLs are turned into their section URLs