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Fastest way to get the first object from a queryset in django?

...ust do the above and it will only pull the first. You could even use .order_by() to ensure you get the first you want. Be sure to add the .get() or else you will get a QuerySet back and not an object. share | ...
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Determine if an object property is ko.observable

...ce) { if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false; if (instance.__ko_proto__ === ko.dependentObservable) return true; return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain }; UPDATE: If you are using KO 2...
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What is the pythonic way to avoid default parameters that are empty lists?

... def my_func(working_list=None): if working_list is None: working_list = [] working_list.append("a") print(working_list) The docs say you should use None as the default and explicitly test for it in the body ...
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Datepicker: How to popup datepicker when click on edittext

...e: <EditText android:id="@+id/Birthday" custom:font="@string/font_avenir_book" android:clickable="true" android:editable="false" android:hint="@string/birthday"/> Now in Java File: final Calendar myCalendar = Calendar.getInstance(); EditText edittext= (EditText) findViewByI...
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How to take the first N items from a generator or list in Python? [duplicate]

...:step] Slicing a generator import itertools top5 = itertools.islice(my_list, 5) # grab the first five elements You can't slice a generator directly in Python. itertools.islice() will wrap an object in a new slicing generator using the syntax itertools.islice(generator, start, stop, step) Rem...
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What is the worst gotcha in C# or .NET? [closed]

...efixes for your private fields (there are others, but this is a good one): _myVar, m_myVar – jrista Jun 26 '09 at 8:01 205 ...
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What does if __name__ == “__main__”: do?

Given the following code, what does the if __name__ == "__main__": do? 33 Answers 33...
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WPF OpenFileDialog with the MVVM pattern? [duplicate]

...ou would consume it. public MyViewModel : ViewModel { private string _selectedPath; public string SelectedPath { get { return _selectedPath; } set { _selectedPath = value; OnPropertyChanged("SelectedPath"); } } private RelayCommand _openCommand; pu...
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How do I clear only a few specific objects from the workspace?

... You'll find the answer by typing ?rm rm(data_1, data_2, data_3) share | improve this answer | follow | ...
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Why do you need explicitly have the “self” argument in a Python method?

...hing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way. share | improve this answer ...