I don&#x27;t mean to be too critical because there was clearly a lot of effort in this write-up, but as a serious question: what value does the post add that&#x27;s not already found at the huge and very popular Stack Overflow page [0] (that this post even links to) about this subject?<p>Particularly, the answer by StackOverflow user `Aaron Hall` upvoted around 680 times [1], also deconstructs and provides eerily similar content as what this post gives (for example, the poorness of the<p><pre><code>    dict(x, **y)
</code></pre>
solution and some performance comparisons).<p>I guess this post does mention itertools.chain and ChainMap ... though I would almost never recommend using those if your goal is to merge two regular dicts. Probably anyone reading the code is going to be baffled unless there was a special reason why generators or ChainMap were needed -- these really don&#x27;t belong in the discussion; they&#x27;re very different.<p>As someone who has used Python almost daily for the past 8 years, I also can&#x27;t help but feel let down when I read more stuff about being so-called &quot;pythonic.&quot; I especially hate it when I see discouraging criticisms on Stack Overflow that seem to scare away newcomers because they didn&#x27;t know you could do a dict comprehension or something. The whole &quot;pythonic&quot; thing is waaayyyy overrated. Just write code that is clean, and if you use a couple of extra lines, or you loop over a range instead of a for-statement treating something as an Iterator, so what, it really, really doesn&#x27;t matter in most cases, and you can always profile and fix the few cases where it does. It <i>certainly</i> doesn&#x27;t matter because of some subjective debates about what is more &quot;readable&quot;, like whether a dict-comprehension is &quot;less readable&quot; than a two-line copy-and-update approach.<p>[0] <a href="http:&#x2F;&#x2F;stackoverflow.com&#x2F;q&#x2F;38987&#x2F;567620" rel="nofollow">http:&#x2F;&#x2F;stackoverflow.com&#x2F;q&#x2F;38987&#x2F;567620</a><p>[1] <a href="http:&#x2F;&#x2F;stackoverflow.com&#x2F;a&#x2F;26853961&#x2F;567620" rel="nofollow">http:&#x2F;&#x2F;stackoverflow.com&#x2F;a&#x2F;26853961&#x2F;567620</a>