Python字典前双星号（**）的作用

import numpy as np
print(np.arange(3,6))
输出：
[3, 4, 5]

import numpy as np
LIST = [3, 6]
print(np.arange(*LIST))
输出：
[3, 4, 5]

def parrot(voltage, state=‘a stiff’, action=‘voom’):
   … print “-- This parrot wouldn’t”, action,
   … print “if you put”, voltage, “volts through it.”,
   … print “E’s”, state, “!”
   …
   d = {“voltage”: “four million”, “state”: “bleedin’ demised”, “action”: “VOOM”}
   parrot(**d)

输出：
– This parrot wouldn’t VOOM if you put four million volts through it. E’s bleedin’ demised !