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How to rename items in values() in Django?
... could use the extra method:
MyModel.objects.extra(
select={
'renamed_value': 'cryptic_value_name'
}
).values(
'renamed_value'
)
This basically does SELECT cryptic_value_name AS renamed_value in the SQL.
Another option, if you always want the renamed version but the db has the cryptic nam...
In C, do braces act as a stack frame?
...'t have to generate code that pushes/pops anything on entry/exit (and generally, they don't).
Also note that local variables may not use any stack space at all: they could be held in CPU registers or in some other auxiliary storage location, or be optimized away entirely.
So, the d array, in theor...
Can I extend a class using more than 1 class in PHP?
...
Answering your edit :
If you really want to fake multiple inheritance, you can use the magic function __call().
This is ugly though it works from class A user's point of view :
class B {
public function method_from_b($s) {
echo $s;
}
}
c...
Using @property versus getters and setters
...
Prefer properties. It's what they're there for.
The reason is that all attributes are public in Python. Starting names with an underscore or two is just a warning that the given attribute is an implementation detail that may not stay the same in future versions of the code. It doesn't preven...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Lua简明教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ble来管理全局变量的，Lua把这些全局变量放在了一个叫“_G”的Table里。
我们可以用如下的方式来访问一个全局变量（假设我们这个全局变量名叫globalVar）：
1
2
_G.globalVar
_G["globalVar"]
我们可...
How do I get the filepath for a class in Python?
...u can use the inspect module, like this:
import inspect
inspect.getfile(C.__class__)
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In Django, how does one filter a QuerySet with dynamic field lookups?
...a custom ModelField/FormField/WidgetField that implemented the behavior to allow the user to, on the GUI side, basically "build" a query, never seeing the actual text, but using an interface to do so. Sounds like a neat project...
– T. Stone
Sep 23 '09 at 20:2...
Where does Chrome store extensions?
...s local paths, they are left in the place where there are selected from in all Operating Systems.
Ex: If i load a unpacked Extension from E:\Chrome Extension the unpacked Extension is still in the same location
Storage Location for Packed Extensions
Navigate to chrome://version/ and look for Prof...
Is Python strongly typed?
...
Python is strongly, dynamically typed.
Strong typing means that the type of a value doesn't change in unexpected ways. A string containing only digits doesn't magically become a number, as may happen in Perl. Every change of type requires an explicit...