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In Django, how do I check if a user is in a certain group?

..., and more directly, you can check if a a user is in a group by: if django_user.groups.filter(name = groupname).exists(): ... Note that groupname can also be the actual Django Group object. share | ...
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When is the @JsonProperty property used and what is it used for?

...ect. Suppose there is an object: public class Parameter { public String _name; public String _value; } The serialization of this object is: { "_name": "...", "_value": "..." } The name of variable is directly used to serialize data. If you are about to remove system api from system im...
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Unable to install Maven on Windows: “JAVA_HOME is set to an invalid directory”

...e-maven-2.2.0\bin" is on your command search path. Make sure that the JAVA_HOME variable refers to the home directory for your Java installation. If you are executing Java from "E:\Sun\SDK\jdk\bin", then the JAVA_HOME variable needs to point to "E:\Sun\SDK\jdk". NB: JAVA_HOME should NOT end with "...
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What is the definition of “interface” in object oriented programming

...dom.randint(0,10) # What you care about class SecretGame(object): def __init__(self, number_generator): number = number_generator.generate() print number Here, none of the classes implement an interface. Python does not care about that, because the SecretGame class will just t...
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How to remove array element in mongodb?

... Try the following query: collection.update( { _id: id }, { $pull: { 'contact.phone': { number: '+1786543589455' } } } ); It will find document with the given _id and remove the phone +1786543589455 from its contact.phone array. You can use $unset to unset the value ...
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Saving images in Python at a very high quality

...his after running the commands to plot the image: plt.savefig('destination_path.eps', format='eps') I have found that eps files work best and the dpi parameter is what really makes them look good in a document. UPDATE: To specify the orientation of the figure before saving simply call the follo...
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How to initialize a vector in C++ [duplicate]

... give you the beginning and end of an array: template <typename T, size_t N> T* begin(T(&arr)[N]) { return &arr[0]; } template <typename T, size_t N> T* end(T(&arr)[N]) { return &arr[0]+N; } And then you can do this without having to repeat the size all over: int vv[]...
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Why can't I use the 'await' operator within the body of a lock statement?

....Tasks; public class SemaphoreLocker { private readonly SemaphoreSlim _semaphore = new SemaphoreSlim(1, 1); public async Task LockAsync(Func<Task> worker) { await _semaphore.WaitAsync(); try { await worker(); } finally {...
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What exactly does @synthesize do?

...then will result in having two ivars, namely someInt plus an autogenerated _someInt variable. Thus self.someInt and someInt will not address the same variables any more. If you don't expect such behavior as I did this might get you some headache to find out. ...
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Best way to give a variable a default value (simulate Perl ||, ||= )

...s called the Null coalescing operator. You can use it like this: $name = $_GET['name'] ?? 'john doe'; This is equivalent to $name = isset($_GET['name']) ? $_GET['name']:'john doe'; share | impr...