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correct way to define class variables in Python [duplicate]
...hey are just two different kinds of class elements:
Elements outside the __init__ method are static elements; they belong to the class.
Elements inside the __init__ method are elements of the object (self); they don't belong to the class.
You'll see it more clearly with some code:
class MyClass...
Import a module from a relative path
...
Assuming that both your directories are real Python packages (do have the __init__.py file inside them), here is a safe solution for inclusion of modules relatively to the location of the script.
I assume that you want to do this, because you need to include a set of modules with your script. I us...
How to determine the version of the C++ standard used by the compiler?
...ngs:
/*Define Microsoft Visual C++ .NET (32-bit) compiler */
#if (defined(_M_IX86) && defined(_MSC_VER) && (_MSC_VER >= 1300)
...
#endif
/*Define Borland 5.0 C++ (16-bit) compiler */
#if defined(__BORLANDC__) && !defined(__WIN32__)
...
#endif
You probably wil...
How does the @property decorator work in Python?
...is just syntactic sugar; the syntax:
@property
def foo(self): return self._foo
really means the same thing as
def foo(self): return self._foo
foo = property(foo)
so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @foo.setter(), what you ...
RuntimeError on windows trying python multiprocessing
...l import (i.e. execute) the main module at start. You need to insert an if __name__ == '__main__': guard in the main module to avoid creating subprocesses recursively.
Modified testMain.py:
import parallelTestModule
if __name__ == '__main__':
extractor = parallelTestModule.ParallelExtrac...
Redirecting to URL in Flask
...eturn a redirect:
import os
from flask import Flask,redirect
app = Flask(__name__)
@app.route('/')
def hello():
return redirect("http://www.example.com", code=302)
if __name__ == '__main__':
# Bind to PORT if defined, otherwise default to 5000.
port = int(os.environ.get('PORT', 5000)...
Best way to organize jQuery/JavaScript code (2013) [closed]
...eplace them with units that are loosely coupled. So, instead of having:
ad_unit1.js
$("#au1").click(function() { ... });
ad_unit2.js
$("#au2").click(function() { ... });
I will have:
ad_unit.js:
var AdUnit = function(elem) {
this.element = elem || new jQuery();
}
AdUnit.prototype....
What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
...
Are nested try/except blocks in python a good programming practice?
...EAFP.
Personally, I prefer to avoid nesting when it's not necessary:
def __getattribute__(self, item):
try:
return object.__getattribute__(item)
except AttributeError:
pass # fallback to dict
try:
return self.dict[item]
except KeyError:
raise Attrib...
Hashing a dictionary?
...d make a frozenset with the dict's items and use hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...