code: def reverse_guard(lst):
      
      rev = {'<': '>=', '>': '=<', '>=': '<', '=<': '>'}
      return [rev[l] if l in rev else l for l in lst]
docs: Reverse guard expression. not
          (@a > 5) ->  (@a =< 5)
      Args:
          lst (list): Expression
      returns:
          list