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Abstract methods in Python [duplicate]
...what a metaclass is, don't worry about it. :-)
– kindall
Dec 8 '10 at 0:15
1
The linked tutorial ...
Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
Is it valid to replace http:// with // in a ?
... we test our sites in Firefox, Safari, IE6, IE7 and Opera. These browsers all understand that URL format.
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How can I get a channel ID from YouTube?
...ube Channel ID from its URL:
https://commentpicker.com/youtube-channel-id.php
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Using property() on classmethods
... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter:
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How to create GUID / UUID?
I'm trying to create globally-unique identifiers in JavaScript. I'm not sure what routines are available on all browsers, how "random" and seeded the built-in random number generator is, etc.
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How do I unset an element in an array in javascript?
...ipt Arrays are not associative arrays like those you might be used to from PHP. If your "array key" is a string, you're no longer operating on the contents of an array. Your array is an object, and you're using bracket notation to access the member named <key name>. Thus:
var myArray = [];
m...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...ut this, but I gave up in the end, as the rules are somewhat diffuse. Basically, you’ll have to get the hang of it.
Perhaps it is best to concentrate on where curly braces and parenthesis can be used interchangeably: when passing parameters to method calls. You may replace parenthesis with curly b...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...