Python3新特性

1、f-strings(3.6+)

first="001"
second="002"
test_msg = f'this is first {first}, this is second {second}.'
print(test_msg)
this is first 001, this is second 002.

2、Type hinting(3.5+)

def abc(a: str) -> bool:
    return a in 'this is a msg'

abc('is')

3、字典顺序得到保证

>>> {"abc": 1, "abd": 3, "abe": 2}
{'abc': 1, 'abd': 3, 'abe': 2}

4、跨进程内存共享
在multiprocessing添加了一个shared_memory模块，支持跨进程间的内存共享。

5、字典合并
old:

dict(x, **y)

new:

{**x, **y}

6、列表推导式优化

# old:
>>> x = 1
>>> [x for x in "abc"]
['a', 'b', 'c']
>>> x  # x 变量被推导式修改
'c'

# new
>>> x = 1
>>> [x for x in "abc"]
['a', 'b', 'c']
>>> x  # x 变量被推导式修改
1