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Queue.Queue vs. collections.deque

...nd collections.deque serve different purposes. Queue.Queue is intended for allowing different threads to communicate using queued messages/data, whereas collections.deque is simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas co...
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Representing and solving a maze given an image

...lection breaks are not false edges introduced by wrong threshold. In fact, all interior points of this maze are accessible from the start. Add artificial borders on the maze to make sure virtual traveler will not walk around it :) Implement breadth-first search (BFS) in your favorite language and ru...
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How do I add a placeholder on a CharField in Django?

... Look at the widgets documentation. Basically it would look like: q = forms.CharField(label='search', widget=forms.TextInput(attrs={'placeholder': 'Search'})) More writing, yes, but the separation allows for better abstraction of more complic...
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Good examples of Not a Functor/Functor/Applicative/Monad?

...but not Applicative: I don't have a good example. There is Const, but ideally I'd like a concrete non-Monoid and I can't think of any. All types are basically numeric, enumerations, products, sums, or functions when you get down to it. You can see below pigworker and I disagreeing about whether ...
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How do I mock a service that returns promise in AngularJS Jasmine unit test?

...ce; beforeEach(module('app.myService')); beforeEach(inject( function(_myService_, myOtherService, $q){ myService = _myService_; spyOn(myOtherService, "makeRemoteCallReturningPromise").and.callFake(function() { var deferred = $q.defer(); deferred.resolve('Remote call res...
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urllib2.HTTPError: HTTP Error 403: Forbidden

...Error, e: print e.fp.read() content = page.read() print content Actually, it works with just this one additional header: 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', share | ...
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What is the instanceof operator in JavaScript?

...ce p inherits from Person.prototype. Per the OP's request I've added a small example with some sample code and an explanation. When you declare a variable you give it a specific type. For instance: int i; float f; Customer c; The above show you some variables, namely i, f, and c. The type...
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How to perform OR condition in django queryset?

... from django.db.models import Q User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True)) via Documentation share | improve this answer | follow ...
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Finding quaternion representing the rotation from one vector to another

... Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
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Default filter in Django admin

How can I change the default filter choice from 'ALL'? I have a field named as status which has three values: activate , pending and rejected . When I use list_filter in Django admin, the filter is by default set to 'All' but I want to set it to pending by default. ...