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super() raises “TypeError: must be type, not classobj” for new-style class
...pe(OldStyle()) is the instance type, which does inherit from object. Basically, an old-style class just creates objects of type instance (whereas a new-style class creates objects whose type is the class itself). This is probably why the instance OldStyle() is an object: its type() inherits from ob...
How to make rpm auto install dependencies
...hip and filesystem permissions:
# chown -R root.root /home/user/repo
Install the createrepo package if not installed yet, and run
# createrepo /home/user/repo
# chmod -R o-w+r /home/user/repo
Create a repository configuration file, e.g. /etc/yum.repos.d/myrepo.repo containing
[local]
name=My Aw...
What is the most efficient way to store a list in the Django models?
...
This is probably what I will end up doing, but I was really hoping the underlying structure for this would have been built in. I guess I am to o lazy.
– grieve
Jul 10 '09 at 16:11
...
How to make a cross-module variable?
...as if a global from any other module that includes __builtin__ -- which is all of them, by default.
a.py contains
print foo
b.py contains
import __builtin__
__builtin__.foo = 1
import a
The result is that "1" is printed.
Edit: The __builtin__ module is available as the local symbol __builtin...
How many GCC optimization levels are there?
..., the default if no optimization level is specified)
-O1 (optimize minimally)
-O2 (optimize more)
-O3 (optimize even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere...
What is the fastest way to get the value of π?
I'm looking for the fastest way to obtain the value of π, as a personal challenge. More specifically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in.
...
What is the difference between _tmain() and main() in C++?
...Now, in UTF-16, the character set used by Windows when Unicode is enabled, all the ASCII characters are represented as the pair of bytes \0 followed by the ASCII value.
And since the x86 CPU is little-endian, the order of these bytes are swapped, so that the ASCII value comes first, then followed b...
git rebase without changing commit timestamps
...branch", using the option --committer-date-is-author-date (introduced initially in Jan. 2009 in commit 3f01ad6
Note that the --committer-date-is-author-date option seems to leave the author timestamp, and set the committer timestamp to be the same as the original author timestamp, which is what the...
How to find list of possible words from a letter matrix [Boggle Solver]
Lately I have been playing a game on my iPhone called Scramble. Some of you may know this game as Boggle. Essentially, when the game starts you get a matrix of letters like so:
...
Compare object instances for equality by their attributes
...s:
>>> x == y
True
Note that implementing __eq__ will automatically make instances of your class unhashable, which means they can't be stored in sets and dicts. If you're not modelling an immutable type (i.e. if the attributes foo and bar may change value within the lifetime of your obje...