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super() raises “TypeError: must be type, not classobj” for new-style class
...pe(OldStyle()) is the instance type, which does inherit from object. Basically, an old-style class just creates objects of type instance (whereas a new-style class creates objects whose type is the class itself). This is probably why the instance OldStyle() is an object: its type() inherits from ob...
Traverse a list in reverse order in Python
... are reversed on the fly while traversing! This is an important feature of all these iteration functions (which all end on “ed”).
– Konrad Rudolph
Feb 9 '09 at 19:10
9
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How to change the name of a Django app?
...e changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
...
Python function overloading
...
What you are asking for is called multiple dispatch. See Julia language examples which demonstrates different types of dispatches.
However, before looking at that, we'll first tackle why overloading is not really what you want in python.
Why Not Overl...
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...
What is the most pythonic way to check if an object is a number?
...and is not iterable" could be a good definition in some cases. But,
you really need to ask yourself, what it is that you're asking that what you want to consider "a number" must definitely be able to do, and what it must absolutely be unable to do -- and check.
This may also be needed in 2.6 or la...
Flask-SQLAlchemy import/context issue
...:
# fields here
pass
And then in your application setup you can call init_app:
# apps.application.py
from flask import Flask
from apps.members.models import db
app = Flask(__name__)
# later on
db.init_app(app)
This way you can avoid cyclical imports.
This pattern does not necessitate ...
How do I capture SIGINT in Python?
...f KeyboardInterruptException is implemented as a SIGINT handler or if it really only catches Ctrl+C presses, but either way, using a signal handler makes your intent explicit (at least, if your intent is the same as OP's). More importantly though, with a signal you don't have to wrap try-catches ar...
Best way to allow plugins for a PHP application
... 5 = 9
4 * 5 = 20
Notes:
For this example source code, you must declare all your plugins before the actual source code that you want to be extendable. I've included an example of how to handle single or multiple values being passed to the plugin. The hardest part of this is writing the actual d...
Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...