#  #



## 1 ##

 list  1  5 

```python
list1 = [1,2,3,4,5]
for num1 in list1 :
    print ( num1 , end = ' ' )
```

 5  1  Python  `reversed()`

```python
list1 = [1,2,3,4,5]
for num1 in reversed(list1) :
    print ( num1 , end = ' ' )
```

** `__reversed__()`  **

 `__reversed__()` 

```python
# -*- coding: UTF-8 -*-

class Countdown:
    def __init__(self, start):
        self.start = start

    def __iter__(self):
    	# Forward iterator
        n = self.start
        while n > 0:
            yield n
            n -= 1

    def __reversed__(self):
    	# Reverse iterator
        n = 1
        while n