Python: None

The usage of None¶

In [2]:

def min(values):
    s=None
    for i in values:
        if s is None or i <s:
            s=i
    return s

In [6]:

min([1,2,3])

Out[6]:

1

In [25]:

min([5,3,7,2,12,7,8,9,11])

Out[25]:

2

In [18]:

x=(None,1,2,3)

In [19]:

x

Out[19]:

(None, 1, 2, 3)

In [20]:

for i in x:
    print(i)

None
1
2
3

In [21]:

x

Out[21]:

(None, 1, 2, 3)

In [22]:

x[2]

Out[22]:

2

In [23]:

x[3]

Out[23]:

3

In [24]:

len(x)

Out[24]:

4