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Why return NotImplemented instead of raising NotImplementedError
...
It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the s...
The import android.support cannot be resolved
...port-v4:YOUR_TARGET_VERSION)"
Navigate to your "build.gradle" inside your App Directory and double check if your desired Android Support Library has been added to your dependencies.
Rebuild your project and now everything should work.
Further reading regarding this Question:
Support Library - ...
Clean way to launch the web browser from shell script?
...
OSX:
$ open -a /Applications/Safari.app http://www.google.com
or
$ open -a /Applications/Firefox.app http://www.google.com
or simply...
$ open some_url
share
...
Python nested functions variable scoping [duplicate]
...When I run your code I get this error:
UnboundLocalError: local variable '_total' referenced before assignment
This problem is caused by this line:
_total += PRICE_RANGES[key][0]
The documentation about Scopes and Namespaces says this:
A special quirk of Python is that – if no global st...
Python memoising/deferred lookup property decorator
...
from boltons.cacheutils import cachedproperty
class Foo(object):
def __init__(self):
self.value = 4
@cachedproperty
def cached_prop(self):
self.value += 1
return self.value
f = Foo()
print(f.value) # initial value
print(f.cached_prop) # cached property is c...
How to avoid explicit 'self' in Python?
...e, and always know whether you are accessing a member or not:
class A(some_function()):
def f(self):
self.member = 42
self.method()
That's the complete code! (some_function returns the type used as a base.)
Another, where the methods of a class are dynamically composed:
class B(objec...
Getting the class name of an instance?
...
Have you tried the __name__ attribute of the class? ie type(x).__name__ will give you the name of the class, which I think is what you want.
>>> import itertools
>>> x = itertools.count(0)
>>> type(x).__name__
'count...
String concatenation vs. string substitution in Python
...e interpolation/templating.
>>> import timeit
>>> def so_q_sub(n):
... return "%s%s/%d" % (DOMAIN, QUESTIONS, n)
...
>>> so_q_sub(1000)
'http://stackoverflow.com/questions/1000'
>>> def so_q_cat(n):
... return DOMAIN + QUESTIONS + '/' + str(n)
...
>>> ...
How can i query for null values in entity framework?
...].[Foos] AS [Extent1]
WHERE (CASE
WHEN (([Extent1].[ProductID] = 1 /* @p__linq__0 */)
AND (NULL /* @p__linq__1 */ IS NOT NULL)) THEN
CASE
WHEN ([Extent1].[ProductStyleID] = NULL /* @p__linq__2 */) THEN cast(1 as bit)
WHEN ([Extent1].[ProductStyleID] <> NULL /* @p__li...
Add support library to Android Studio project
...dencies {
classpath 'com.android.tools.build:gradle:0.5.+'
}
}
apply plugin: 'android'
repositories {
mavenCentral()
}
dependencies {
compile 'com.android.support:support-v4:13.0.+'
}
android {
compileSdkVersion 18
buildToolsVersion "18.0.1"
defaultConfig {
...