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Get all related Django model objects

...his gives you the property names for all related objects: links = [rel.get_accessor_name() for rel in a._meta.get_all_related_objects()] You can then use something like this to get all related objects: for link in links: objects = getattr(a, link).all() for object in objects: # d...
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What's the best way to parse command line arguments? [closed]

...ter on. Here's a typical line to add an option to your parser: parser.add_option('-q', '--query', action="store", dest="query", help="query string", default="spam") It pretty much speaks for itself; at processing time, it will accept -q or --query as options, store the ar...
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select and update database record with a single queryset

... Use the queryset object update method: MyModel.objects.filter(pk=some_value).update(field1='some value') share | improve this answer | follow | ...
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Upgrading PHP in XAMPP for Windows?

...e\bin with the newer versions. Now the trick: take the files which have a '_2' in their names (for example php5apache2_2.dll or php5apache2_2_filter.dll), copy them in the apache\bin subdirectory and remove the '_2' part, overwriting the existing files. This is necessary because by XAMPP uses Apache...
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What is the 'override' keyword in C++ used for? [duplicate]

... : base { virtual void foo() override { std::cout << __PRETTY_FUNCTION__ << std::endl; } }; int main() { base* override = new derived(); override->foo(); return 0; } Output: zaufi@gentop /work/tests $ g++ -std=c++11 -o override-test override-test.cc...
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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values

... operator. if ((unsigned)(number-lower) <= (upper-lower)) in_range(number); With a typical, modern computer (i.e., anything using twos complement), the conversion to unsigned is really a nop -- just a change in how the same bits are viewed. Note that in a typical case, you can pre-...
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Installing PDO driver on MySQL Linux server

...-get install php5-mysql There is no limitation between using PDO and mysql_ simultaneously. You will however need to create two connections to your DB, one with mysql_ and one using PDO. share | im...
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What is the difference between Θ(n) and O(n)?

... one is Big "O" one is Big Theta http://en.wikipedia.org/wiki/Big_O_notation Big O means your algorithm will execute in no more steps than in given expression(n^2) Big Omega means your algorithm will execute in no fewer steps than in the given expression(n^2) When both condition are tru...
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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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Should import statements always be at the top of a module?

...ent libraries, don't break if an optional library is not installed. In the __init__.py of a plugin, which might be imported but not actually used. Examples are Bazaar plugins, which use bzrlib's lazy-loading framework. shar...