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How to read the database table name of a Model instance?

... Found the answer myself: the _meta attribute of an instance has the information: model_instance._meta.db_table share | improve this answer | ...
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Why declare a struct that only contains an array in C?

... It allows you to pass the array to a function by value, or get it returned by value from a function. Structs can be passed by value, unlike arrays which decay to a pointer in these contexts. ...
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Scala @ operator

...n itself? That would be accomplished with this: o match { case x @ Some(_) => println(x) case None => } Note that @ can be used at any level, not just at the top level of the matching. share | ...
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How to compare type of an object in Python?

Basically I want to do this: 14 Answers 14 ...
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How to sort with a lambda?

...nclude <iostream> #include <sstream> struct Foo { Foo() : _i(0) {}; int _i; friend std::ostream& operator<<(std::ostream& os, const Foo& f) { os << f._i; return os; }; }; typedef std::vector<Foo> VectorT; std::string ...
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Convert Python dictionary to JSON array

... If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call. >>> json.dumps(your_data, ensure_ascii=False) If ensure_ascii is false, then the return value will be a unicode instance subject to normal Python str to unicode coercion rules in...
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What is the difference between .text, .value, and .value2?

...presenting what is displayed on the screen for the cell. Using .Text is usually a bad idea because you could get #### .Value2 gives you the underlying value of the cell (could be empty, string, error, number (double) or boolean) .Value gives you the same as .Value2 except if the cell was formatted...
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Can dplyr package be used for conditional mutating?

...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA. df %>% mutate(g = 2 * (a == 2 ...
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How to make a class conform to a protocol in Swift?

...aSource' Is expected. You will get the error until your class implements all required methods of the protocol. So get coding :) share | improve this answer | follow ...
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Efficient evaluation of a function at every cell of a NumPy array

...t be faster than the "manual" double loop iteration and assignment through all the array elements. Especially, because it stores the result to a newly created variable (and not directly to the initial input). Thanks a lot for your reply though:) – Peter Oct 9 '...