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How do Python's any and all functions work?
...([]) == True
– JavaSa
Jan 22 '19 at 21:22
1
@JavaSa You can explicitly check if the list is empty...
if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation bool()...
How can you profile a Python script?
...
21
It is also worth noting that you can use the cProfile module from ipython using the magic function %prun (profile run). First import your m...
Why does Python code use len() function instead of a length method?
... len(..)
– alternative
Nov 7 '11 at 21:13
41
...
Insert into … values ( SELECT … FROM … )
...ke it more readable.
– Banjocat
Oct 21 '14 at 15:32
2
...
How do I get a list of column names from a psycopg2 cursor?
...it’s not (easily) possible to get column names for views from information_schema.
– wjv
Jun 23 '16 at 7:30
6
...
How to install therubyracer gem on 10.10 Yosemite?
...
mmlnmmln
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2
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What does `m_` variable prefix mean?
...
answered Oct 21 '12 at 14:56
MichaelHouseMichaelHouse
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Windows下如何判断Win32 or x64？ - C/C++ - 清泛网 - 专注C/C++及内核技术
...判断Win32 or x64？MSDN 里说，VC 有 3 个预处理常量，分别是 _WIN32，_WIN64，WIN32。这三个常量如何使用呢？看起来简单，其实是很困惑的。 在 Win3...MSDN 里说，VC 有 3 个预处理常量，分别是 _WIN32，_WIN64，WIN32。这三个常量如何使用...
How to keep a Python script output window open?
...w.
Add code to wait at the end of your script. For Python2, adding ...
raw_input()
... at the end of the script makes it wait for the Enter key. That method is annoying because you have to modify the script, and have to remember removing it when you're done. Specially annoying when testing other ...