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How to import a Python class that is in a directory above?
...from within pkg.subpkg1 you will import pkg.subpkg2.mod. The specification for relative imports is contained within PEP 328.
PEP 328 deals with absolute/relative imports.
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addEventListener not working in IE8
...lse {
_checkbox.attachEvent("onclick", setCheckedValues);
}
Update::
For Internet Explorer versions prior to IE9, attachEvent method should be used to register the specified listener to the EventTarget it is called on, for others addEventListener should be used.
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Batch File; List files in directory, only filenames?
...tory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names and exclude anything else.
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Best way to select random rows PostgreSQL
...equential scan of the big table, only an index scan.
First, get estimates for the main query:
SELECT count(*) AS ct -- optional
, min(id) AS min_id
, max(id) AS max_id
, max(id) - min(id) AS id_span
FROM big;
The only possibly expensive part is the count(*) (for h...
How to download a file from a URL in C#?
... Though I think that WebClient seems like a much more straightforward and simple solution.
– StormsEngineering
Oct 1 '19 at 23:17
3
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What is “:-!!” in C code?
...
@weston Lots of different places. See for yourself!
– John Feminella
Feb 10 '12 at 16:06
170
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What is the difference between AF_INET and PF_INET in socket programming?
... thought that maybe a address family (what the "AF" in "AF_INET" stands
for) might support several protocols that were referenced by their
protocol family (what the "PF" in "PF_INET" stands for).
That didn't happen. Oh well. So the correct thing to do is to use AF_INET in your
struct sockad...
Best way to structure a tkinter application? [closed]
...ented approach. This is the template that I start out with:
# Use Tkinter for python 2, tkinter for python 3
import tkinter as tk
class MainApplication(tk.Frame):
def __init__(self, parent, *args, **kwargs):
tk.Frame.__init__(self, parent, *args, **kwargs)
self.parent = parent
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not None test in Python [duplicate]
...
if val is not None:
# ...
is the Pythonic idiom for testing that a variable is not set to None. This idiom has particular uses in the case of declaring keyword functions with default parameters. is tests identity in Python. Because there is one and only one instance of Non...
Return a value if no rows are found in Microsoft tSQL
... returned. I'd prefer that false (0) is returned in that scenario. Looking for the simplest method to account for no records.
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