code: def get_capitalized_relname(tree, subtree_index):
      
      match = HS2015_REL_RE.match(tree[subtree_index].label())
      relname = match.group('relname')
      return relname.capitalize()
docs: Returns the capitalized relation name from a tree's satellite
      subtree label, e.g. 'satellite:contrast' becomes 'Contrast'.