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Create a “with” block on several context managers? [duplicate]
...rite:
with A() as X, B() as Y, C() as Z:
do_something()
This is normally the best method to use, but if you have an unknown-length list of context managers you'll need one of the below methods.
In Python 3.3, you can enter an unknown-length list of context managers by using contextlib.Exit...
C++ STL Vectors: Get iterator from index?
...
Generally, you can use the same arithmetic with STL iterators than with pointers. They are designed to be exchangeable when using STL algorithms.
– Vincent Robert
Mar 22 '09 at 21:07
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Code Golf: Collatz Conjecture
...sp+0x04], 2
jne .usage
mov ebx, [esp+0x08]
push dword [ebx+0x04]
call atoi
add esp, 4
cmp eax, 0
je .usage
mov ebx, eax
push eax
push msg
.loop:
mov [esp+0x04], ebx
call printf
test ebx, 0x01
jz .even
.odd:
lea ebx, [1+ebx*2+ebx]
jmp .loop
.even:
shr ebx, 1
...
Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
Checking if a string can be converted to float in Python
...False
print(isfloat("12.34.56")) False Two dots not allowed.
print(isfloat("#56")) False
print(isfloat("56%")) False
print(isfloat("0E0")) True
print(isfloat("x86E0")) False
print(isfloat("86-5")) ...
Fixed point vs Floating point number
...oint and floating point numbers due to hard to read definitions about them all over Google. But none that I have read provide a simple enough explanation of what they really are. Can I get a plain definition with example?
...
How to open emacs inside bash
...
Thanks, Tikhon! That's been pissing me off all day :P
– speeves
Jan 5 '12 at 23:27
add a comment
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Python error “ImportError: No module named”
Python is installed in a local directory.
28 Answers
28
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Get absolute path of initially run script
...tioning that, reading the documentation, there is no mention that the initially run script's path is the first item of the array returned by get_included_files(). I suggest to store __FILE__ into a constant at the beginning of the script meant to be initially run.
– Paolo
...
Using cURL with a username and password?
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@CristianVrabie Technically correct, but incorrect if you're running it from an automated script that doesn't allow prompts. Would be curious about a solution to that problem.
– Ligemer
Mar 12 '14 at 23:29
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