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Unique fields that allow nulls in Django

...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None: class FooForm(forms.ModelForm): class Meta: model = Foo def clean_bar(self): return self.cleaned_data['bar'] or None class FooAdmin(admin.ModelAdmin...
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Where is the Keytool application?

...achine, you would normally find the jdk at C:\Program Files\Java\jdk1.8.0_121\bin It is used for managing keys and certificates you can sign things with, in your case, probably a jar file. If you provide more details of what you need to do, we could probably give you a more specific answer. ...
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What's the shortest code to cause a stack overflow? [closed]

... All these answers and no Befunge? I'd wager a fair amount it's shortest solution of them all: 1 Not kidding. Try it yourself: http://www.quirkster.com/iano/js/befunge.html EDIT: I guess I need to explain this one. The 1 o...
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How to check whether a string is Base64 encoded or not

... for PHP5 //where $json is some data that can be base64 encoded $json=some_data; //this will check whether data is base64 encoded or not if (base64_decode($json, true) == true) { echo "base64 encoded"; } else { echo "not base64 encoded"; } Use this for PHP7 //$strin...
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Convert a char to upper case using regular expressions (EditPad Pro)

...m using EditPad Pro (however I am willing to use any other tool that would allow me to do this, as long as it is free to try, since I only need to do this once). ...
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YouTube API to fetch all videos on a channel

...rly because it only spends 2 quota points instead of 100 (that the search call would spend). – JP de la Torre Nov 12 '16 at 10:28 1 ...
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Ruby convert Object to Hash

... instance_values can be used for all ruby objects for the similar output. – bishal Jan 22 '19 at 11:37 add a comment ...
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Get Slightly Lighter and Darker Color from UIColor

...so, from @Riley's idea, it may be a better idea to make the color proprtionally darker or lighter instead of adding or subtracting constant values. As @jrturton pointed out, it's not necessary to manipulate the RGB components; it's better to modify the brightness property itself. All in all: @imple...
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How can I create tests in Android Studio?

...ow testing works. If you follow along for the next 10 minutes, you will be all set up to start adding your tests to your own app. I think you'll be surprised how easy it is. I certainly was. Intro to Android Testing There are two different types of tests that you will do. Local unit tests. These ar...
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How to convert byte array to string and vice versa?

... This might work, but you should avoid using String constructor at all cost. – hfontanez Jun 26 '17 at 17:13 t...