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ImportError: No module named Crypto.Cipher
When I try to run app.py (Python 3.3, PyCrypto 2.6) my virtualenv keeps returning the error listed above. My import statement is just from Crypto.Cipher import AES . I looked for duplicates and you might say that there are some, but I tried the solutions (although most are not even solutions) and n...
How to establish a connection pool in JDBC?
...
Usually if you need a connection pool you are writing an application that runs in some managed environment, that is you are running inside an application server. If this is the case be sure to check what connection pooling facil...
What is the advantage of GCC's __builtin_expect in if else statements?
...
I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
What is private bytes, virtual bytes, working set?
...se values are a reliable indicator of how much memory an executable is actually using, and none of them are really appropriate for debugging a memory leak.
Private Bytes refer to the amount of memory that the process executable has asked for - not necessarily the amount it is actually using. They ...
Short description of the scoping rules?
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Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — N...
Correct use of Multimapping in Dapper
...ID,
CustomerName.
This makes the spliton: parameter not so useful, especially when you're not sure what order the columns are returned in. Of course you could manually specify columns...but it's 2017 and we just rarely do that anymore for basic object gets.
What we do, and it's worked great fo...
Fastest way to list all primes below N
...4.0 |
| sundaram3 | 416.0 |
+---------------------+-------+
Of all the methods tested, allowing numpy, for n=1000000,
primesfrom2to was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| primesfrom2to | 15.9 |
| p...
Creating the Singleton design pattern in PHP5
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/**
* Singleton class
*
*/
final class UserFactory
{
/**
* Call this method to get singleton
*
* @return UserFactory
*/
public static function Instance()
{
static $inst = null;
if ($inst === null) {
$inst = new UserFactory();
...
How to make an immutable object in Python?
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Can you use namedtuple internally inside the class instead of instantiating the object externally? I'm very new to python but the advantage to your other answer is that I can have a class hide the details and also have the power of things like optional p...
How to debug Lock wait timeout exceeded on MySQL?
In my production error logs I occasionally see:
11 Answers
11
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