Double asterisk in function parameters

Question

Found this one on challenge:
def func(**qwerty):
print(qwerty["one"])
func(a=0, one=173)
Output--> '173'
questions:
1) Why and when are double asterisk used in function arguments?
2) why at line 2 of funtion the qwerty parameter is given as a list[]?
thank you in advance for help.

Answer 1

With * you are passing a bunch of values in tuple format and can then access them from the function.
With ** you pass keyworded values in dictionary format:
{'one': 173, 'two': 0,... }
And dictionary objects you access by dictname['key'].

Answer 2

check this link here is full explanation.
https://stackoverflow.com/questions/36901/what-does-double-star-asterisk-and-star-asterisk-do-for-parameters