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How do I detect the Python version at runtime? [duplicate]
...o.
For example, to check that you are running Python 3.x, use
import sys
if sys.version_info[0] < 3:
raise Exception("Must be using Python 3")
Here, sys.version_info[0] is the major version number. sys.version_info[1] would give you the minor version number.
In Python 2.7 and later, the ...
Remove all the elements that occur in one list from another
...es exactly what you want and stores the result in l3:
l3 = [x for x in l1 if x not in l2]
l3 will contain [1, 6].
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How to test if list element exists?
I would like to test if an element of a list exists, here is an example
7 Answers
7
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Performing Breadth First Search recursively
...s, to implement something that follows the semantics of BFS at some cost. If the cost of comparison is expensive but node traversal is cheap, then as @Simon Buchan did, you can simply run an iterative depth-first search, only processing the leaves. This would mean no growing queue stored in the he...
How to check if an option is selected?
... what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ...
The non jQuery (arguably best practice) way to do it would be:
$('#mySelectBox option').each(function() {
if(this.selected) ...
Although, if you are just looking for the selected value...
don't fail jenkins build if execute shell fails
...ild process, I am running a git commit as an execute shell step. However, if there are no changes in the workspace, Jenkins is failing the build. This is because git is returning an error code when there are no changes to commit. I'd like to either abort the build, or just mark it as unstable if t...
Should import statements always be at the top of a module?
...s within a function will cause calls to that function to take longer.
So if you care about efficiency, put the imports at the top. Only move them into a function if your profiling shows that would help (you did profile to see where best to improve performance, right??)
The best reasons I've see...
How to wait until an element exists?
...ionObserver((mutations) => {
mutations.forEach((mutation) => {
if (!mutation.addedNodes) return
for (let i = 0; i < mutation.addedNodes.length; i++) {
// do things to your newly added nodes here
let node = mutation.addedNodes[i]
}
})
})
observer.observe(documen...
Reimport a module in python while interactive
... object, so it must have been successfully imported before. This is useful if you have edited the module source file using an external editor and want to try out the new version without leaving the Python interpreter.
If running Python 3.4 and up, do import importlib, then do importlib.reload(name...
How to calculate number of days between two given dates?
If I have two dates (ex. '8/18/2008' and '9/26/2008' ), what is the best way to get the number of days between these two dates?
...