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How to avoid having class data shared among instances?
...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other.
– Matt Moriarity
Nov 5 '09 at 14:04
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MySQL vs MongoDB 1000 reads
...very excited about MongoDb and have been testing it lately. I had a table called posts in MySQL with about 20 million records indexed only on a field called 'id'.
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How to create module-wide variables in Python? [duplicate]
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Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
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...
Delete directory with files in it?
I wonder, what's the easiest way to delete a directory with all its files in it?
33 Answers
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MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in there?
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Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
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What does multicore assembly language look like?
...on, but it's an answer to a question that appears in the comments. Essentially, the question is what support the hardware gives to multi-threaded operation.
Nicholas Flynt had it right, at least regarding x86. In a multi threaded environment (Hyper-threading, multi-core or multi-processor), the B...
Using python's eval() vs. ast.literal_eval()?
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datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
How do i find out what all symbols are exported from a shared object?
I have a shared object(dll). How do i find out what all symbols are exported from that?
9 Answers
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