What is the best way to add entries from 1 dictionary to another?

[bowlofred]

With a list, you can append a new value into the list.

>>> l = [1, 2]
>>> l.append(3)
>>> l
[1, 2, 3]

With a dict, you can add a key/value pair that wasn't there before, or you can update it with another dict, and that either add or changes the values of any matching keys.

>>> d = {'a': 1, 'b': 2}
>>> d['c'] = 3
>>> d.update({'d': 4})
>>> d
{'a': 1, 'b': 2, 'c': 3, 'd': 4}