code: function isUsed (name) {
          if (module.isUsed(name)) {
            return true
          }
          if (dupes.length > 0) {
            return dupes.some((dupe) => {
              const m = analyzer.modules.get(dupe.file)
              return m && m.isUsed(name)
            })
          }
          return false
        }
docs: Check if a name was used in this module, or in any of this module's deduped versions.