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How to write header row with csv.DictWriter?

...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...
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Markdown open a new window link [duplicate]

... common features of HTML. One of its best features is that you can always fallback to the full syntax for HTML. This includes doing things that aren't included in markdown. Personally, I like that markdown is concise and includes very little fluff. It makes it easier to learn the whole set of short...
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Adding new column to existing DataFrame in Python pandas

... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable. – Paniz Apr 27 '19 at 22:42 ...
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Test PHP headers with PHPUnit

...78 Error: Class 'PHPUnit_Util_Configuration' not found in - on line 378 Call Stack: 0.0013 582512 1. {main}() -:0 Try add this to your bootstrap file to fix it: <?php if (!defined('PHPUNIT_COMPOSER_INSTALL')) { define('PHPUNIT_COMPOSER_INSTALL', __DIR__ . '/path/to/composer/ven...
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Why are unnamed namespaces used and what are their benefits?

...ng directive already took place. This means you can have free functions called (for example) help that can exist in multiple translation units, and they won't clash at link time. The effect is almost identical to using the static keyword used in C which you can put in in the declaration of identif...
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What is a regular expression for a MAC Address?

...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
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Immutable vs Mutable types

... Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
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Can a C# lambda expression have more than one statement?

... (I'm assuming you're really talking about multiple statements rather than multiple lines.) You can use multiple statements in a lambda expression using braces, but only the syntax which doesn't use braces can be converted into an expression tree: ...
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How to calculate moving average using NumPy?

...5, 13.5, 14.5, 15.5, 16.5, 17.5]) So I guess the answer is: it is really easy to implement, and maybe numpy is already a little bloated with specialized functionality. share | improve this an...
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What's the better (cleaner) way to ignore output in PowerShell? [closed]

...ad and > $null has about a 0.3% overhead. Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different: Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]}) And no...