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How can I open multiple files using “with open” in Python?

I want to change a couple of files at one time, iff I can write to all of them. I'm wondering if I somehow can combine the multiple open calls with the with statement: ...
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What is the use case of noop [:] in bash?

... to do. while keep_waiting; do : # busy-wait done The : builtin dates all the way back to the Thompson shell, it was present in Unix v6. : was a label indicator for the Thompson shell's goto statement. The label could be any text, so : doubled up as a comment indicator (if there is no goto comm...
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The 'Access-Control-Allow-Origin' header contains multiple values

...rties.Settings.Default.Cors, "", "")) as well as app.UseCors(CorsOptions.AllowAll); on the server. This results in two header entries. Just use the latter one and it works. share | improve this a...
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Are (non-void) self-closing tags valid in HTML5?

... In HTML 4, <foo / (yes, with no > at all) means <foo> (which leads to <br /> meaning <br>> (i.e. <br>>) and <title/hello/ meaning <title>hello</title>). This is an SGML rule that browsers did a very poor job of su...
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How can I echo HTML in PHP?

I want to conditionally output HTML to generate a page, so what's the easiest way to echo multiline snippets of HTML in PHP 4+? Would I need to use a template framework like Smarty? ...
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Error type 3 Error: Activity class {} does not exist

...the Build directory Restarted Android Studio Rebuild the Project Run Optionally (Go to the files menu on android, click on "Invalidate Caches / Restart..." uninstall the app on your phone and try again) And everything worked fine! I think the key is to restart your IDE. Hope this helps you or a...
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How many bytes does one Unicode character take?

...ing, it defines codepoints and a codepoint is a number, associated with usually a character. I say usually because there are concepts like combining characters. You may be familiar with things like accents, or umlauts. Those can be used with another character, such as an a or a u to create a new log...
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Is there a way to change the environment variables of another process in Unix?

...t one process can change another's environment variables (assuming they're all being run by the same user)? A general solution would be best, but if not, what about the specific case where one is a child of the other? ...
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I do not want to inherit the child opacity from the parent in CSS

... Opacity is not actually inherited in CSS. It's a post-rendering group transform. In other words, if a <div> has opacity set you render the div and all its kids into a temporary buffer, and then composite that whole buffer into the page ...
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Why are regular expressions so controversial? [closed]

...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs. – Pacerier Dec 1 '15 at 21:53 ...