Modern Python Standard Library Cookbook

How to do it...

The steps for this recipe are:

1. Given a function, f, we want to pass the arguments from two dictionaries, d1 and d2 as follows:

>>> def f(a, b, c, d):...     print (a, b, c, d)...>>> d1 = dict(a=5, b=6)>>> d2 = dict(b=7, c=8, d=9)

2. collections.ChainMap can help us achieve what we want; it can cope with duplicated entries and works with any Python version:

>>> f(**ChainMap(d1, d2))
5 6 8 9

3. In Python 3.5 and newer versions, you can also create a new dictionary by combining multiple dictionaries through the literal syntax, and then pass the resulting dictionary as the argument of the function:

>>> f(**{**d1, **d2})
5 7 8 9

4. In this case, the duplicated entries are accepted too, but are handled in reverse order of priority to ...