字典合并
dict(a,**b)
Python 中两个字典(dict)合并 - dkcndk - 博客园 https://www.cnblogs.com/dkblog/archive/2012/02/02/2336089.html
merge two dicts
Python 3.6.4
>>> x={'a':1,'b':2}
>>> y={'b':3,'c':4}
>>> z={**x,**y}
>>> z
{'a': 1, 'b': 3, 'c': 4}
>>> z={**y,**x}
>>> z
{'b': 2, 'c': 4, 'a': 1}
>>>