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What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...
Python using enumerate inside list comprehension
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Just to be really clear, this has nothing to do with enumerate and everything to do with list comprehension syntax.
This list comprehension returns a list of tuples:
[(i,j) for i in range(3) for j in 'abc']
this a list of dicts:
[{i:...
How to count occurrences of a column value efficiently in SQL?
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If you're using Oracle, then a feature called analytics will do the trick. It looks like this:
select id, age, count(*) over (partition by age) from students;
If you aren't using Oracle, then you'll need to join back to the counts:
select a.id, a.age, b.age_co...
How to compare two dates?
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@Emadpres: imagine this was typed manually. The past line was typed first, while the present line was typed second... so the past line was entered first, so past < present is True.
– ramcdougal
Mar 20 '17 at 15:50
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What is the difference between ? and Object in Java generics?
...is right way to go to use ResponseEntity<?> on controller level for all my controller functions?
– Irakli
Nov 25 '16 at 7:38
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What is difference between cacerts and keystore?
...he keystore. (Confusingly, the same file format is used for both and it's called a keystore file.)
– Marquis of Lorne
Jul 29 '13 at 23:44
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How can I wait for a thread to finish with .NET?
I've never really used threading before in C# where I need to have two threads, as well as the main UI thread. Basically, I have the following.
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Test if a class has an attribute?
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to only check if the attribute is present, which is usually all that is needed for parameterless/propertyless attributes, it's cheaper to use .IsDefined, as it will query the metadata, and not deserialize and instantiate the attribute object.
– Lasse V. Karl...
CSS table column autowidth
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Instead of manually adding the '.last' class, you can just do 'td:last-child' as the selector.
– T.Ho
Feb 13 '13 at 0:34
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Aligning a float:left div to center?
I want to have a group of images display horizontally across the page. Each image has a few link below it so I need to put a container around each image/link-group.
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