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How can I create a copy of an object in Python?
...elf)(self.a, self.b)
def __deepcopy__(self, memo): # memo is a dict of id's to copies
id_self = id(self) # memoization avoids unnecesary recursion
_copy = memo.get(id_self)
if _copy is None:
_copy = type(self)(
deepcopy(self.a, memo),
...
In a django model custom save() method, how should you identify a new object?
...t self._state is not a private instance variable, but named that way to avoid conflicts, checking self._state.adding is now the preferable way to check.
self.pk is None:
returns True within a new Model object, unless the object has a UUIDField as its primary_key.
The corner case you might have...
NSUserDefaults not cleared after app uninstall on simulator
.... I have implemented the following code in my rootViewController 's viewDidLoad method:
7 Answers
...
Is there a native jQuery function to switch elements?
...it will be moved before the target (not cloned)".
– Ridcully
Jan 11 '12 at 15:55
12
I like this o...
Create singleton using GCD's dispatch_once in Objective-C
...(instancetype)sharedInstance
{
static dispatch_once_t once;
static id sharedInstance;
dispatch_once(&once, ^
{
sharedInstance = [self new];
});
return sharedInstance;
}
+ (Class*)sharedInstance
{
static dispatch_once_t once;
static Class *sharedInst...
How to show a dialog to confirm that the user wishes to exit an Android Activity?
...
In Android 2.0+ this would look like:
@Override
public void onBackPressed() {
new AlertDialog.Builder(this)
.setIcon(android.R.drawable.ic_dialog_alert)
.setTitle("Closing Activity")
.setMessage("Are you ...
Django - limiting query results
...dler(logging.StreamHandler())
In [23]: User.objects.all().order_by('-id')[:10]
(0.000) SELECT "auth_user"."id", "auth_user"."username", "auth_user"."first_name", "auth_user"."last_name", "auth_user"."email", "auth_user"."password", "auth_user"."is_staff", "auth_user"."is_active", "au...
Navigation in django
...ad>
<body>
...
{% block nav %}
<ul id="nav">
<li>{% block nav-home %}<a href="{% url home %}">Home</a>{% endblock %}</li>
<li>{% block nav-about %}<a href="{% url about %}">About</a>{% endblo...
How to reshape data from long to wide format
...
Using reshape function:
reshape(dat1, idvar = "name", timevar = "numbers", direction = "wide")
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Recommendations of Python REST (web services) framework? [closed]
...mendations of different Python-based REST frameworks for use on the serverside to write your own RESTful APIs? Preferably with pros and cons.
...