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Gevent Pool/Group Alike in Python3 Asyncio

Python3 Asyncio implements an event loop, but in quite low level, it's missing some basic helpers that can make your life a lot easier.

The Pool and Group are typical missing ones. Compare these codes below

Simple Loop

• without group

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  "signature": "sha256:f7fc0e66200bb5a9cae8e5e59abfaa99691caa881252e9266f11e7cffc7dafe6"
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 "worksheets": [
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seeing this puzzle in glowing's jobs page

https://glowing.com/jobs/mobiledeveloper#mtop

here's my solution

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Using Reids As Database

Redis is very performant, due to performance consideration, sometimes we need to use Redis as a database, when querying a redis database, we need to consider indexing and filtering.

Single Index

We can use SortedSet as Index.

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import time
from collections import deque

def throttled_call(func, args=(), kwargs={}, threshold_per_minute=60):
    """Throttling the function call with ``threshold_per_minute`` calls per minute. 

    This is useful when the function request a remote service that having throttling policy. 
    We must honor the throttling, otherwise we will be banned.

    :param func: the function to be called

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def chop(matrix, box, direction, results=None):
    if results is None:
        results = []
    x1, y1, x2, y2 = box
    w = x2 - x1 + 1
    h = y2 - y1 + 1
    if w <= 0 or h <= 0:
        return results
    else:
        if direction == 0:

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Running redis using upstart on Ubuntu

I've been trying to understand how to setup systems from the ground up on Ubuntu. I just installed redis onto the box and here's how I did it and some things to look out for.

To install:

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#! /bin/sh
### BEGIN INIT INFO
# Provides:		redis-server
# Required-Start:	$syslog
# Required-Stop:	$syslog
# Should-Start:		$local_fs
# Should-Stop:		$local_fs
# Default-Start:	2 3 4 5
# Default-Stop:		0 1 6
# Short-Description:	redis-server - Persistent key-value db

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# ElasticSearch Service
description     "ElasticSearch"

start on (net-device-up
          and local-filesystems
          and runlevel [2345])

stop on runlevel [016]

respawn

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/*
Pretty Date script modified from John Resig here http://ejohn.org/blog/javascript-pretty-date
*/
    function relativeDateTime (tdate) {
        var system_date;
        if (typeof (tdate) === "number") {
            tdate = new Date(tdate).toString();
        }

        if (navigator.userAgent.match(/MSIE\s([^;]*)/)) {