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Why do I get AttributeError: 'NoneType' object has no attribute 'something'?
...The sort() method of a list sorts the list in-place, that is, mylist is modified. But the actual return value of the method is None and not the list sorted. So you've just assigned None to mylist. If you next try to do, say, mylist.append(1) Python will give you this error.
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What's the difference between deque and list STL containers?
What is the difference between the two? I mean the methods are all the same. So, for a user, they work identically.
8 Answ...
How can I return pivot table output in MySQL?
... from there in here (even more since I just don't want to copy their vast knowledge), but I'll give some advice on how to deal with pivot tables the sql way generally with the example from peku who asked the question in the first place.
Maybe the link comes back soon, I'll keep an eye out for it.
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Image Greyscale with CSS & re-color on mouse-over?
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If said images need to be linked to other website tho, how could this be done if the images are set as backgrounds?
– Meta
Sep 1 '11 at 17:39
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Difference between DirectCast() and CType() in VB.NET
...ld with a C# (int) cast. But you can cast from an IEnumerable to an array, if your underlying IEnumerable object variable really is an Array. And of course you can cast from Object to anything, assuming the type of your object instance really is somewhere below your cast type in the inheritance tree...
How to avoid 'cannot read property of undefined' errors?
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Update:
If you use JavaScript according to ECMAScript 2020 or later, see optional chaining.
TypeScript has added support for optional chaining in version 3.7.
// use it like this
obj?.a?.lot?.of?.properties
Solution for JavaScr...
PHP script to loop through all of the files in a directory?
...ike to be able to sort the files by name, type or by date created/added/modified. (Think fancy directory "index".) I'd also like to be able to add exclusions to the list of files, such as the script itself or other "system" files. (Like the . and .. "directories".)
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Difference between JSON.stringify and JSON.parse
...pt object into JSON text and stores that JSON text in a string, eg:
var my_object = { key_1: "some text", key_2: true, key_3: 5 };
var object_as_string = JSON.stringify(my_object);
// "{"key_1":"some text","key_2":true,"key_3":5}"
typeof(object_as_string);
// "string"
JSON.parse turns a...
How to loop backwards in python? [duplicate]
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range() and xrange() take a third parameter that specifies a step. So you can do the following.
range(10, 0, -1)
Which gives
[10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
But for iteration, you should really be using xrange instead. So,
xrange(10, 0, -1)
Note for Python 3 users:...
Is there a way to create multiline comments in Python?
...iting features can be a painful experience. Finding the right editor (and knowing how to use it) can make a big difference in how the Python programming experience is perceived.
Not only should the text editor be able to comment-out selected regions, it should also be able to shift blocks of code t...