如何获取包含字典的值和键的列表？

Question

I am trying to understand what's the most efficient way for producing a list containing the values and the keys of a dictionary. I've tried using .items() function but with poor results because items() returns a list of tuples that then I have to flatten importing other modules. At the moment I am using:

zdict = { 'a':1,'b':2,'c':3}
mylistofvaluesandkeys = list(zdict) + list(zdict.keys()))

The result I am looking is a list eg [1, 2, 3, 'a', 'b', 'c'] where I've all the elements in any order.

Is there a better way to perform this task?

Answer 1

You can do it lazily with itertools :

>>> import itertools
>>> itertools.chain(zdict.values(), zdict.keys())
<itertools.chain object at 0x10a25a9d0>
>>> list(itertools.chain(zdict.values(), zdict.keys()))
[1, 2, 3, 'a', 'b', 'c']

Answer 2

If it is acceptable to have keys mixed with values you can simply do this:

from itertools import chain

list(chain(*zdict.items()))

This is the result:

['a', 1, 'b', 2, 'c', 3]