docs: def trim1(l, proportiontocut, tail='right'):
      """
  Slices off the passed proportion of items from ONE end of the passed
  list (i.e., if proportiontocut=0.1, slices off 'leftmost' or 'rightmost'
  10% of scores).  Slices off LESS if proportion results in a non-integer
  slice index (i.e., conservatively slices off proportiontocut).
  
  Usage:   ltrim1 (l,proportiontocut,tail='right')  or set tail='left'
  Returns: trimmed version of list l
  """
      if tail == 'right':
          lowercut = 0
          uppercut = len(l) - int(proportiontocut * len(l))
      elif tail == 'left':
          lowercut = int(proportiontocut * len(l))
          uppercut = len(l)
      return l[lowercut:uppercut]