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I'm getting Key error in python
...ts?
From the official python docs:
exception KeyError
Raised when a mapping (dictionary) key is not found in the set of
existing keys.
For example:
>>> mydict = {'a':'1','b':'2'}
>>> mydict['a']
'1'
>>> mydict['c']
Traceback (most recent call last):
File "<...
How can I search for a multiline pattern in a file?
I needed to find all the files that contained a specific string pattern. The first solution that comes to mind is using find piped with xargs grep :
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Re-enabling window.alert in Chrome
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Note that you must close all the tabs of the same domain where you opted out of that alert option.
– Miguel
May 4 '17 at 10:36
1
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Git cherry pick vs rebase
... the distinction indeed became somewhat moot, but this is something to be called convergent evolution ;-)
The true distinction lies in original intent to create both tools:
git rebase's task is to forward-port a series of changes a developer has in their private repository, created against versio...
How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
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First off, a "port" is just a number. All a "connection to a port" really represents is a packet which has that number specified in its "destination port" header field.
Now, there are two answers to your question, one for stateful protocols and one for stateless...
Generate a heatmap in MatPlotLib using a scatter data set
...50 heatmap. If you want, say, 512x384, you can put bins=(512, 384) in the call to histogram2d.
Example:
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Showing line numbers in IPython/Jupyter Notebooks
...l line numbers. In more recent notebook versions Shift-L should toggle for all cells.
If you can't remember the shortcut, bring up the command palette Ctrl-Shift+P (Cmd+Shift+P on Mac), and search for "line numbers"), it should allow to toggle and show you the shortcut.
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find vs find_by vs where
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Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
Is there a generator version of `string.split()` in Python?
...plitlines chops off the trainling newline though (something that I don't really like...); if you wanted to replicated that part of the behavior, you could use grouping: (m.group(2) or m.group(3) for m in re.finditer('((.*)\n|(.+)$)', s)). PS: I guess the outer paren in the RE are not needed; I just ...
List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...