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How to get a random value from dictionary in python
...b': 5}
>>> d.popitem()
('c', 7)
Since the dict doesn't preserve order, by using popitem you get items in an arbitrary (but not strictly random) order from it.
Also keep in mind that popitem removes the key-value pair from dictionary, as stated in the docs.
popitem() is useful to dest...
When should we call System.exit in Java
...and the shutdown process in java, in addition to the answer above:
In an orderly* shutdown, the JVM first starts all registered shutdown hooks. Shutdown hooks are unstarted threads that are registered with Runtime.addShutdownHook.
JVM makes no guarantees on the order in which shutdown hooks
are st...
Real World Example of the Strategy Pattern
... of comments, etc), and in case management doesn't yet know exactly how to order, and may want to experiment with different orderings at a later date. You make an interface (IOrderAlgorithm or something) with an order method, and let an Orderer-object delegate the ordering to a concrete implementati...
SSL certificate is not trusted - on mobile only [closed]
...ates on your server (and not only one) and these need to be in the correct order. If they are there but not in the correct order, the website will be fine on desktop browsers (an iOs as well I think), but android is more strict about the order of certificates, and will give an error if the order is ...
setImmediate vs. nextTick
...t loop, preventing any I/O from occurring. setImmediates are queued in the order created, and are popped off the queue once per loop iteration. This is different from process.nextTick which will execute process.maxTickDepth queued callbacks per iteration. setImmediate will yield to the event loop af...
MySQL DROP all tables, ignoring foreign keys
...ed to make porting easier. In MySQL 5.5, they do nothing."
Therefore, in order for the drop statements to work if you need:
SET FOREIGN_KEY_CHECKS = 0
This will disable referential integrity checks - so when you are done performing the drops you need, you will want to reset key checking with
S...
eval command in Bash and its typical uses
... as a text file, reads each line of text, and uses eval to execute them in order. That's essentially the same behavior as the bash source statement, which is what one would use, unless it was necessary to perform some kind of transformation (e.g. filtering or substitution) on the content of the impo...
MySQL indexes - what are the best practices?
...tant to understand what's going on.
Broadly speaking, an index imposes an ordering on the rows of a table.
For simplicity's sake, imagine a table is just a big CSV file. Whenever a row is inserted, it's inserted at the end. So the "natural" ordering of the table is just the order in which rows...
How to convert an OrderedDict into a regular dict in python3
I am struggling with the following problem:
I want to convert an OrderedDict like this:
8 Answers
...
List directory tree structure in python?
... Nice tool, do you have a quick example on how to use criteria in order to exclude folder names?
– Matt-Mac-Muffin
Nov 2 '19 at 22:00
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