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Django Rest Framework: Dynamically return subset of fields
...verride the serializer __init__ method and set the fields attribute dynamically, based on the query params. You can access the request object throughout the context, passed to the serializer.
Here is a copy&paste from Django Rest Framework documentation example on the matter:
from rest_framew...
capturing self strongly in this block is likely to lead to a retain cycle
...
Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
Get key by value in dictionary
...oes not imply that it was not intended to be used as such. Not helpful at all.
– Tropicalrambler
Jan 8 at 17:52
Would...
What is the difference between “instantiated” and “initialized”?
... it to be. The value is what you assign to it.
Variables are Initialized
All variables are always given an initial value at the point the variable is declared. Thus all variables are initialized.
For value types, like int the compiler will give them a valid value if you do not do so explicitly. i...
Setting PayPal return URL and making it auto return?
... if they don't have Auto Return enabled there, the buyer would need to manually click past the end of checkout in order to be redirected to that URL, rather than being redirected automatically.
– SubGothius
Aug 11 '16 at 20:58
...
How to pretty-print a numpy.array without scientific notation and with given precision?
...335 0.712]
And suppress suppresses the use of scientific notation for small numbers:
y=np.array([1.5e-10,1.5,1500])
print(y)
# [ 1.500e-10 1.500e+00 1.500e+03]
np.set_printoptions(suppress=True)
print(y)
# [ 0. 1.5 1500. ]
See the docs for set_printoptions for other options.
T...
How to ignore user's time zone and force Date() use specific time zone
...
A Date object's underlying value is actually in UTC. To prove this, notice that if you type new Date(0) you'll see something like: Wed Dec 31 1969 16:00:00 GMT-0800 (PST). 0 is treated as 0 in GMT, but .toString() method shows the local time.
Big note, UTC stands ...
Regular expression to find URLs within a string
...
It's 2017, and unicode domain names are all over the place. \w may not match international symbols (depends on regex engine), the range is needed instead: a-zA-Z0-9\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF.
– Michael Antipin
Aug...
Debugging in Clojure? [closed]
...
There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (f...
Try catch statements in C
... exceptions but you can simulate them to a degree with setjmp and longjmp calls.
static jmp_buf s_jumpBuffer;
void Example() {
if (setjmp(s_jumpBuffer)) {
// The longjmp was executed and returned control here
printf("Exception happened here\n");
} else {
// Normal code execution s...