Only return branches that exist in the ttree when using selection_to_branches about optimization HOT 1 CLOSED

      branchesSpecified = list(set(itertools.chain.from_iterable(selection_to_branches(supercut['selections'], tree) for supercut in supercuts)))
      eventWeightBranchesSpecified = list(set(selection_to_branches(eventWeightBranch, tree)))

      # get actual list of branches in the file
      availableBranches = tree_get_branches(tree, eventWeightBranchesSpecified)

      # remove anything that doesn't exist
      branchesToUse = [branch for branch in branchesSpecified if branch in availableBranches]
      branchesSkipped = list(set(branchesSpecified) - set(branchesToUse))