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Why is __init__() always called after __new__()?
...it__ takes self as parameter. Until you create instance there is no self.
Now, I gather, that you're trying to implement singleton pattern in Python. There are a few ways to do that.
Also, as of Python 2.6, you can use class decorators.
def singleton(cls):
instances = {}
def getinstance(...
“There was an error while performing this operation”
...ssue and resolved in exactly same way as you suggested and all works again now. in our case we upgraded server from windows 2012 to windows 2016.
– Davide Piras
Jan 12 '18 at 10:52
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Form inside a form, is that alright? [duplicate]
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This is good to know. I've implemented it in the past with custom data attributes and javascript when I could have just included a html5 shim library.
– Jon Hulka
Mar 22 '17 at 18:10
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What is the best way to trigger onchange event in react js
...is needed I found this comment very helpful:
The input logic in React now dedupe's change events so they don't fire
more than once per value. It listens for both browser onChange/onInput
events as well as sets on the DOM node value prop (when you update the
value via javascript). This has...
CSS image resize percentage of itself?
... This doesn't resize the image to 50% of it's original size, it's now 50% of the parent of img_wrap..
– Wesley
May 25 '12 at 9:46
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Determining 32 vs 64 bit in C++
...h what we think is a reasonable solution using macros, but was curious to know if people could think of cases where this might fail or if there is a better way to do this. Please note we are trying to do this in a cross-platform, multiple compiler environment.
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How to do version numbers? [closed]
...nswer", I started working on the article again. PDF and LaTeX versions are now available, a complete rewrite including better language and explanatory graphics will follow as soon as I can find the time. Thank you for your votes!
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Controlling a USB power supply (on/off) with Linux
... USB power management from kernels 2.6.32, which seem to settle in 2.6.38. Now you'll need to wait for the device to become idle, which is governed by the particular device driver. The driver needs to support it, otherwise the device will never reach this state. Unluckily, now the user has no chance...
data.table vs dplyr: can one do something well the other can't or does poorly?
...ters. As Grace Hopper would say, Mind your nanoseconds!
3. Syntax
Let's now look at syntax. Hadley commented here:
Data tables are extremely fast but I think their concision makes it harder to learn and code that uses it is harder to read after you have written it ...
I find this remark poi...
Run an untrusted C program in a sandbox in Linux that prevents it from opening files, forking, etc.?
...t.c root/assignment.c
Exit the VM's root FS:
cd ..
sudo umount mountpoint
Now the image is ready, we just need to run it. It will compile and run the submission after booting.
mkfifo /tmp/guest_output
Open a seperate terminal and start listening for guest output:
dd if=/tmp/guest_output bs=1
In an...