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How to combine two or more querysets in a Django view?

...sets into a list is the simplest approach. If the database will be hit for all querysets anyway (e.g. because the result needs to be sorted), this won't add further cost. from itertools import chain result_list = list(chain(page_list, article_list, post_list)) Using itertools.chain is faster than...
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Usage of __slots__?

What is the purpose of __slots__ in Python — especially with respect to when I would want to use it, and when not? 11 A...
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Get all related Django model objects

How can I get a list of all the model objects that have a ForeignKey pointing to an object? (Something like the delete confirmation page in the Django admin before DELETE CASCADE). ...
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Convert Django Model object to dict with all of the fields intact

How does one convert a Django Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False . ...
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How to set the prototype of a JavaScript object that has already been instantiated?

...n set of rules. This is currently unresolved but at least it will be officially part of JavaScript's specification. This question is a lot more complicated than it seems on the surface, and beyond most peoples' pay grade in regards to knowledge of Javascript internals. The prototype property of an...
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What do all of Scala's symbolic operators mean?

...se of teaching, into four categories: Keywords/reserved symbols Automatically imported methods Common methods Syntactic sugars/composition It is fortunate, then, that most categories are represented in the question: -> // Automatically imported method ||= // Syntactic sugar ++= // Syn...
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Relative imports in Python 2.7

... not determine what package Python thinks it is in. That depends, additionally, on how you load the file into Python (by running or by importing). There are two ways to load a Python file: as the top-level script, or as a module. A file is loaded as the top-level script if you execute it directl...
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Iterate over object attributes in python

...foo = 1 ... bar = 'hello' ... def func(self): ... return 'call me' ... >>> obj = Cls() calling dir on the object gives you back all the attributes of that object, including python special attributes. Although some object attributes are callable, such as methods. >>&...
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Relationship between SciPy and NumPy

SciPy appears to provide most (but not all [1]) of NumPy's functions in its own namespace. In other words, if there's a function named numpy.foo , there's almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object. ...
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Print all properties of a Python Class [duplicate]

...rint for example in order of declaration, and you do not want to do it manually, check this – Matteo A Aug 14 '15 at 8:41 ...