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Check if key exists and iterate the JSON array using Python
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If all you want is to check if key exists or not
h = {'a': 1}
'b' in h # returns False
If you want to check if there is a value for key
h.get('b') # returns None
Return a default value if actual value is missing
h.get('b'...
How would you access Object properties from within an object method? [closed]
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PHP offers a myriad of ways to handle this, including magic methods __get and __set, but I prefer explicit getters and setters. Here's why:
Validation can be placed in setters (and getters for that matter)
Intellisense works with explicit methods
No question whether a property is read only,...
Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
How to write a caption under an image?
...line-block;
}
figcaption {
margin: 10px 0 0 0;
font-variant: small-caps;
font-family: Arial;
font-weight: bold;
color: #bb3333;
}
figure {
padding: 5px;
}
img:hover {
transform: scale(1.1);
-ms-transform: scale(1.1);
-webkit-transform: scale(1.1);
...
Lombok is not generating getter and setter
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When starting with a fresh eclipse installation you, in fact, need to "install" Lombok before being able to use it.
Go where you Lombok jar is (e.g. (e.g. you can find in ~/.m2/repository/org/projectlombok/lombok/1.16.10/lombok-1.16.10.jar), run it (Example: jav...
Completion handler for UINavigationController “pushViewController:animated”?
...rface UINavigationController (CompletionHandler)
- (void)completionhandler_pushViewController:(UIViewController *)viewController
animated:(BOOL)animated
completion:(void (^)(void))completion;
@end
Implementation:
#import "UIN...
Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...
Validate decimal numbers in JavaScript - IsNumeric()
...(I had to consider also exponential notation, etc.), a Number object, virtually anything could be passed to that function, I couldn't make any type assumptions, taking care of type coercion (eg. +true == 1; but true shouldn't be considered as "numeric").
I think is worth sharing this set of +30 un...
Include jQuery in the JavaScript Console
...ebsite I would like to get the number of rows in a table. I know this is really easy with jQuery.
20 Answers
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How can I find the version of the Fedora I use?
...something like:
$ source /etc/os-release
$ echo $ID
fedora
$ echo $VERSION_ID
17
$ echo $VERSION
17 (Beefy Miracle)
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