How to copy a dict and modify it in one line of code

Question

Very often I need to create dicts that differ one from another by an item or two. Here is what I usually do:

setup1 = {\'param1\': val1, 
            \'param         


        

Answer 1

I like this line (after from itertools import chain):

d3 = dict(chain(d1.items(), d2.items()))

(Thanks for juanpa.arrivillaga for the improvement!)