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How to write inline if statement for print?
... condition:
block
if expression (introduced in Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly ...
How can I filter a date of a DateTimeField in Django?
...
Such lookups are implemented in django.views.generic.date_based as follows:
{'date_time_field__range': (datetime.datetime.combine(date, datetime.time.min),
datetime.datetime.combine(date, datetime.time.max))}
Because it is quite verbose there are pla...
Java GUI frameworks. What to choose? Swing, SWT, AWT, SwingX, JGoodies, JavaFX, Apache Pivot? [close
...l necessary platforms supported? Can you package the native DLLs with your app?
See here, how to do this for SWT.
If you have a choice here, you should prefer Qt over SWT. Qt has been developed by people who understand UI and the desktop while SWT has been developed out of necessity to make Eclips...
Override Python's 'in' operator?
...
MyClass.__contains__(self, item)
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Remove all occurrences of a value from a list?
...ython 3.x
>>> x = [1,2,3,2,2,2,3,4]
>>> list(filter((2).__ne__, x))
[1, 3, 3, 4]
or
>>> x = [1,2,3,2,2,2,3,4]
>>> list(filter(lambda a: a != 2, x))
[1, 3, 3, 4]
Python 2.x
>>> x = [1,2,3,2,2,2,3,4]
>>> filter(lambda a: a != 2, x)
[1, 3, 3...
Create a GUID in Java
...many bits in a UUID, you can generate many millions of such values in your app and still sleep well. Using one of the other variants further reduces the possibility of collisions even closer to zero because of using "space and time", [1] MAC address or name, and [2] current date-time, as constraints...
How to set timer in android?
...ary.
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.Handler.Callback;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public...
What does $_ mean in PowerShell?
...ich is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value.
...
How enumerate all classes with custom class attribute?
...ugh all the classes in all the assemblies that are loaded into the current app domain. To do that, you would call the GetAssemblies method on the AppDomain instance for the current app domain.
From there, you would call GetExportedTypes (if you only want public types) or GetTypes on each Assembly ...
namedtuple and default values for optional keyword arguments
...Node()
Node(val=None, left=None, right=None)
Before Python 3.7
Set Node.__new__.__defaults__ to the default values.
>>> from collections import namedtuple
>>> Node = namedtuple('Node', 'val left right')
>>> Node.__new__.__defaults__ = (None,) * len(Node._fields)
>&g...