docs: def evaluate_rpn(rpn):
      """
      Evaluates the RPN form produced my map2rpn.
  
      Returns:
          bool
      """
      vals_stack = []
  
      for item in rpn:
  
          if item in _ALL_OPS:
              # Apply the operator and push to the task.
              v2 = vals_stack.pop()
  
              if item in _UNARY_OPS:
                  res = _UNARY_OPS[item](v2)
  
              elif item in _BIN_OPS:
                  v1 = vals_stack.pop()
                  res = _BIN_OPS[item](v1, v2)
              else:
                  raise ValueError("%s not in unary_ops or bin_ops" % str(item))
  
              vals_stack.append(res)
  
          else:
              # Push the operand
              vals_stack.append(item)
  
          #print(vals_stack)
  
      assert len(vals_stack) == 1
      assert isinstance(vals_stack[0], bool)
  
      return vals_stack[0]