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Django Rest Framework File Upload
...r case 2) you can have a single key called data and send the whole json as string in value.
The first method would work out of the box if you have simple fields, but will be a issue if you have nested serializes. The multipart parser wont be able to parse the nested fields.
Below i am providing t...
What __init__ and self do on Python?
...to declare it explicitly. When you create an instance of the A class and call its methods, it will be passed automatically, as in ...
a = A() # We do not pass any argument to the __init__ method
a.method_a('Sailor!') # We only pass a single argument
The __init__ method is roughly w...
How can I maintain fragment state when added to the back stack?
... back stack. However, when I return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue:
...
What is the meaning of “$” sign in JavaScript
...t can be almost anything but is usually "JQuery".
However, in ES6 it is a string interpolation operator in a template "literal" eg.
var s = "new" ; // you can put whatever you think appropriate here.
var s2 = `There are so many ${s} ideas these days !!` ; //back-ticks not quotes
console.log(s2) ;...
ROW_NUMBER() in MySQL
...e about that in the answer a tic ago. You can usually easily drop unwanted extra rows in the application layer afterwards on some random basis, but if you have a lot of rows all with the same col3 it can be problematic.
– bobince
Dec 13 '09 at 0:18
...
What are some compelling use cases for dependent method types?
... type Resource <: BasicResource
trait BasicResource {
def hash : String
def duplicates(r : Resource) : Boolean
}
def create : Resource
// Test methods: exercise is to move them outside ResourceManager
def testHash(r : Resource) = assert(r.hash == "9e47088d")
def testDuplic...
In Flux architecture, how do you manage Store lifecycle?
...
In a Flux app there should only be one Dispatcher. All data flows through this central hub. Having a singleton Dispatcher allows it to manage all Stores. This becomes important when you need Store #1 update itself, and then have Store #2 update itself based on both the Acti...
Please explain the exec() function and its family
... family have different behaviours:
l : arguments are passed as a list of strings to the main()
v : arguments are passed as an array of strings to the main()
p : path/s to search for the new running program
e : the environment can be specified by the caller
You can mix them, therefore you have:
...
What's the bad magic number error?
...the pyc file or trying to run a pyc from a different version of python (usually later) than your interpreter.
If they are your pyc files, just delete them and let the interpreter re-compile the py files. On UNIX type systems, that could be something as simple as:
rm *.pyc
or:
find . -name '*.py...
How to sort with a lambda?
... return os;
};
};
typedef std::vector<Foo> VectorT;
std::string toString(const VectorT& v)
{
std::stringstream ss;
std::copy(v.begin(), v.end(), std::ostream_iterator<Foo>(ss, ", "));
return ss.str();
};
int main()
{
VectorT v(10);
std::for_each(v.be...