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How to retry after exception?
... a nice way to retry a block of code on failure.
For example:
@retry(wait_random_min=1000, wait_random_max=2000)
def wait_random_1_to_2_s():
print("Randomly wait 1 to 2 seconds between retries")
share
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...
What is Lazy Loading?
...:
...
@property
def total(self):
if not hasattr(self, "_total"):
self._total = self.quantity \
+ sum(bi.quantity for bi in self.borroweditem_set.all())
return self._total
Basically, I have an Item class which represents an item in our inven...
python list in sql query as parameter
... cursor.execute(f'SELECT name FROM students WHERE id IN ({','.join('?' for _ in l)})', l). @bobince, you should also remark in your solution that using ? is the safe way to go in terms of avoid SQL injection. There are a lot of answers here that are vulnerable, basically any that concatenates string...
Guaranteed lifetime of temporary in C++?
... a "full-expression" in this case: printf("%s", strdup(std::string("$$$").c_str()) ); ?I mean if strdup(std::string("$$$").c_str()) is taken as the full expression, then the pointer that strdup sees is valid. If std::string("$$$").c_str() is a full expression, then the pointer that strdup sees is in...
App Inventor 2 OCR文字识别教程 - 百度云与本地识别方案 · App Inventor 2 中文网
...费1000次
2. 获取Access Token
global 百度API_KEY = "your-api-key"
global 百度SECRET_KEY = "your-secret-key"
when Screen1.Initialize {
var Token_URL = "https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials" +
"&client_id=" + 百度API_KEY +
...
Is there a performance difference between i++ and ++i in C++?
... this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) // called for i++
{
Foo tmp(*this); // variable "tmp" cannot be optimized away by the compiler
++(*this);
return tmp;
}
Since the compiler isn't generating code, but just calling an operator++ ...
How to set the Default Page in ASP.NET?
..."index.aspx" type="RedirectHandler"/>
//RedirectHandler.cs in your App_Code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
/// <summary>
/// Summary description for RedirectHandler
/// </summary>
public class RedirectHandler : IHttpHandler
{
...
Is there any way to post events to Google Analytics via server-side API? [closed]
... $aParams['qt'] = 0;
//Client ID
$aParams['cid'] = substr(md5($_SERVER['REMOTE_ADDR'].$_SERVER['HTTP_USER_AGENT']), 0, 8);
//User ID
//$aParams['uid'] = '';
//Session Control
//$aParams[''] = '';
//IP Override
$aParams['uip'] = $_SERVER['REMOTE_ADDR'];
//U...
In C, do braces act as a stack frame?
... int big[100000000];
foo(big);
}
bar();
}
gives:
_foobar:
pushl %ebp
movl %esp, %ebp
movl $400000008, %eax
call __alloca
cmpl $0, 8(%ebp)
je L2
leal -400000000(%ebp), %eax
movl %eax, (%esp)
call _foo
L2:
ca...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
... [^0-9] Any single character that's not a digit
\w [a-zA-Z0-9_] Any word character
\W [^a-zA-Z0-9_] Any non-word character
\s [ \r\t\n\f] Any space character
\S [^ \r\t\n\f] Any non-space character
\n [\n] New line
Example 1: Run as macro
The following...