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Calling a class function inside of __init__

... Call the function in this way: self.parse_file() You also need to define your parse_file() function like this: def parse_file(self): The parse_file method has to be bound to an object upon calling it (because it's not a static method). This is done by calling t...
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How exactly does work?

...ly. If you use defer, you can't rely on the script files being executed in order in some browsers. – Flimm Jan 20 '16 at 11:23 2 ...
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How do I add a placeholder on a CharField in Django?

...t specify the field (e.g. for some dynamic method), you can use this: def __init__(self, *args, **kwargs): super(MyForm, self).__init__(*args, **kwargs) self.fields['email'].widget.attrs['placeholder'] = self.fields['email'].label or 'email@address.nl' It also allows the placeholder to de...
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error LNK2019: 无法解析的外部符号_socket,该符号在函数 中被引用 - C/C+...

error LNK2019: 无法解析的外部符号_socket,该符号在函数 中被引用1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4,该符号在函数 _main 中被引用1>NetClient.obj : error L...1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@...
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How to len(generator()) [duplicate]

...e advantages over functions that return lists. However, you could len(list_returning_function()) . Is there a way to len(generator_function()) ? ...
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What's the difference between a Python “property” and “attribute”?

...ggs) it looks up eggs in spam, and then examines eggs to see if it has a __get__, __set__, or __delete__ method — if it does, it's a property. If it is a property, instead of just returning the eggs object (as it would for any other attribute) it will call the __get__ method (since we were ...
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Why is using “for…in” for array iteration a bad idea?

...er inherited properties, a thing that sometimes is not desired. Also, the order of iteration is not guaranteed by the spec., meaning that if you want to "iterate" an array object, with this statement you cannot be sure that the properties (array indexes) will be visited in the numeric order. For e...
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How to check if the string is empty?

... the fact that empty sequences are false. So you should use: if not some_string: or: if some_string: Just to clarify, sequences are evaluated to False or True in a Boolean context if they are empty or not. They are not equal to False or True. ...
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How to access parent scope from within a custom directive *with own scope* in AngularJS?

..." ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'"> <option>--</option> </select> app.js var app = angular.module('plunker', []); app.directive('sdItemsFilter', function() { return { restrict: 'E', scope: { items: '='...
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How to automatically generate a stacktrace when my program crashes

...nclude <unistd.h> void handler(int sig) { void *array[10]; size_t size; // get void*'s for all entries on the stack size = backtrace(array, 10); // print out all the frames to stderr fprintf(stderr, "Error: signal %d:\n", sig); backtrace_symbols_fd(array, size, STDERR_FILENO)...