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How to pass a user defined argument in scrapy spider
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The above code is only partially working for me. For eg. If I define domain using self.domain, I'm still not able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working with the CrawlSpider class
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How do I create a constant in Python?
...t declare a variable or value as constant in Python. Just don't change it.
If you are in a class, the equivalent would be:
class Foo(object):
CONST_NAME = "Name"
if not, it is just
CONST_NAME = "Name"
But you might want to have a look at the code snippet Constants in Python by Alex Martelli.
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How to manage local vs production settings in Django?
...sed in both, but some of them (like paths to static files) need to remain different, and hence should not be overwritten every time the new code is deployed.
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NSInvocation for Dummies?
...send the addObject: message as follows:
[myArray addObject:myString];
Now, let's say you want to use NSInvocation to send this message at some other point in time:
First, you would prepare an NSInvocation object for use with NSMutableArray's addObject: selector:
NSMethodSignature * mySignatur...
How do I print a double value with full precision using cout?
So I've gotten the answer to my last question (I don't know why I didn't think of that). I was printing a double using cout that got rounded when I wasn't expecting it. How can I make cout print a double using full precision?
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Python: Best way to add to sys.path relative to the current running script
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If you don't want to edit each file
Install you library like a normal python libray
or
Set PYTHONPATH to your lib
or if you are willing to add a single line to each file, add a import statement at top e.g.
import import_...
[精华]VC++对话框程序打印及打印预览的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
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void CMyPrintPreviewDlg::OnButton1()
{
// TODO: Add your control notification handler code here
CMyFrame* pf=new CMyFrame(this);
}
2、增加新类：
用ClassWizard新建CMyFrame类（基类CFrameWnd）,功能上相当于文档/视图的应用程序的框架窗口类
用ClassWizard...
Using os.walk() to recursively traverse directories in Python
..._recurse(self, parent_path, file_list, prefix, output_buf, level):
if len(file_list) == 0 \
or (self.max_level != -1 and self.max_level <= level):
return
else:
file_list.sort(key=lambda f: os.path.isfile(os.path.join(parent_path, f)))
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What is the difference between user and kernel modes in operating systems?
...inology).
Entered with the svc instruction (SuperVisor Call), previously known as swi before unified assembly, which is the instruction used to make Linux system calls. Hello world ARMv8 example:
hello.S
.text
.global _start
_start:
/* write */
mov x0, 1
ldr x1, =msg
ldr x2, =len
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What to put in a python module docstring? [closed]
...ion are roughly equivalent to help in terms of amount of information). So if you have in x.py:
"""This module does blah blah."""
class Blah(object):
"""This class does blah blah."""
then:
>>> import x; help(x)
shows:
Help on module x:
NAME
x - This module does blah blah.
FI...