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Referring to the null object in Python
...t;> NoneType = type(None)
>>> id(None)
10748000
>>> my_none = NoneType()
>>> id(my_none)
10748000
>>> another_none = NoneType()
>>> id(another_none)
10748000
>>> def function_that_does_nothing(): pass
>>> return_value = function_that_...
Using Django time/date widgets in custom form
... the proper field names from your model):
from django import forms
from my_app.models import Product
from django.contrib.admin import widgets
class ProductForm(forms.ModelForm):
class Meta:
model = Product
def __init__(self, *args, **kwargs):
...
How to do a less than or equal to filter in Django queryset?
...
Less than or equal:
User.objects.filter(userprofile__level__lte=0)
Greater than or equal:
User.objects.filter(userprofile__level__gte=0)
Likewise, lt for less than and gt for greater than. You can find them all in the documentation.
...
When to use a key/value store such as Redis instead/along side of a SQL database?
...ngle threaded and so forth. I think that another big difference is that in order to take advantage of Redis in your production environment you don't need to switch to Redis. You can just use it in order to do new things that were not possible before, or in order to fix old problems.
Use cases the ...
How to convert a scala.List to a java.util.List?
...1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asList in that example is not necessary if the type expected is a Java List,...
How do I delete rows in a data frame?
...ld generally avoid deleting rows by numeric position. This is because the order of the rows in your data may change in the future. A general principle of a data.frame or database tables is that the order of the rows should not matter. If the order does matter, this should be encoded in an actual va...
How can I uninstall an application using PowerShell?
...
$app = Get-WmiObject -Class Win32_Product | Where-Object {
$_.Name -match "Software Name"
}
$app.Uninstall()
Edit: Rob found another way to do it with the Filter parameter:
$app = Get-WmiObject -Class Win32_Product `
-Filter "N...
Where in a virtualenv does the custom code go?
...our packages right inside:
/foobar
/bin
{activate, activate.py, easy_install, python}
/include
{python2.6/...}
/lib
{python2.6/...}
/mypackage1
__init__.py
/mypackage2
__init__.py
The advantage of this approach is that you can always be sure to find find the activate...
How to do joins in LINQ on multiple fields in single join
...r a second from clause) IMO. You could do some particularly funky magic by ordering one side or the other to find matches more efficiently, but that would be a lot of work - I'd only do that kind of thing after checking whether performance is an issue.
...
After Installing Java JDK 7 For Mac OS X - mvn -version still shows java version 1.6.0_31
...ly found the answer here:
http://www.adam-bien.com/roller/abien/entry/java_se_development_kit_7
You should use JAVA_HOME=$(/usr/libexec/java_home) instead on a Mac and then set the current jdk via "Java Preferences.app".
Set JAVA_HOME in ~/.profile
...