Working Ninja
2017-03-15T07:38:50
dd if=<path to input file> | pv -s <size e.g. 1377M> | dd of=<path to target device>

Source: https://superuser.com/questions/351814/how-to-copy-an-iso-image-onto-usb-with-dd#351815

2017-03-03T07:10:38
Programming as an intellectual activity is the only art form that allows you to create interactive art. You can create projects that other people can play with, and you can talk to them indirectly. No other art form is quite this interactive. Movies flow to the audience in one direction. Paintings do not move. Code goes both ways.

Zed A. Shaw, Learn Python The Hard Way

2017-02-16T15:41:13
#!/usr/bin/python
import sys


try: 
    hex_val = str(sys.argv[1])
except Exception as e:
    sys.exit('Please provide a hex code as an argument (e.g. hex2rgb 333333).')

r = int(hex_val[0:2], 16)
g = int(hex_val[2:4], 16)
b = int(hex_val[4:6], 16)

print('{}, {}, {}'.format(r, g, b))

Append your ~/.bash_aliases with:

alias hex2rgb="~/bin/hex2rgb.py"

Load the new alias:

$ source ~/.bash_aliases

Now we're able to convert Hex to RGB from the command line:

$ hex2rgb e1e1e1
255, 255, 255
2017-02-10T16:39:53

Somehow, somewhere, something happened to my migrations. It had been a few months since I had edited my models.py file and out of the blue I ended up with an issue adding an additional field to a model. I search around Stack Overflow and found a great answer that resolves this (hopefully it doesn't happen to you!). Here's what the recommendation was:

./manage.py migrate --fake <app-name> zero
rm -rf <app-name>/migrations
./manage.py makemigrations <app-name>
./manage.py migrate --fake <app-name>

If you ran into this issue at the same time that I did (when adding a new field to a model), comment out the field you just added before you run any of the above commands (also comment out any additional new changes you may have made). If you don't, the last migrate --fake will include your new field/changes without generating a new migration file for it.

Source: https://stackoverflow.com/questions/23755523/how-to-reset-migrations-in-django-1-7

2017-02-04T16:02:28

To swap control and command, add the following to your ~/.Xmodmap file:

remove control = Control_L
remove mod4 = Super_L Super_R

keysym Control_L = Super_L
keysym Super_L = Control_L
keysym Super_R = Control_L

add control = Control_L Control_R
add mod4 = Super_L Super_R

The above current works for both an Apple laptop and an Apple keyboard.

Also, to use Command+Tab to cycle windows, make sure to update keyboard shortcuts to use Ctrl+Tab instead of Alt+Tab (for Xfce, Window Manager -> Keyboard). All other keyboard shortcuts should come through (from the Control to Command swap perspective).

Source: https://stackoverflow.com/questions/7099602/cmd-control-keys-swap-in-ubuntu

2017-01-10T07:34:45

Why is programming fun? What delights may its practitioner expect as his reward?

First is the sheer joy of making things. As the child delights in his mud pie, so the adult enjoys building things, especially things of his own design. I think this delight must be an image of God's delight in making things, a delight shown in the distinctness and newness of each leaf and each snowflake.

Second is the pleasure of making things that are useful to other people. Deep within, we want others to use our work and to find it helpful. In this respect the programming system is not essentially different from the child's first clay pencil holder "for Daddy's office."

Third is the fascination of fashioning complex puzzle-like objects of interlocking moving parts and watching them work in subtle cycles, playing out the consequences of principles built in from the beginning. The programmed computer has all the fascination of the pinball machine or the jukebox mechanism, carried to the ultimate.

Fourth is the joy of always learning, which springs from the nonrepeating nature of the task. In one way or another the problem is ever new, and its solver learns something: sometimes practical, sometimes theoretical, and sometimes both.

Finally, there is the delight of working in such a tractable medium. The programmer, like the poet, works only slightly removed from pure thought-stuff. He builds his castles in the air, from air, creating by exertion of the imagination. Few media of creation are so flexible, so easy to polish and rework, so readily capable of realizing grand conceptual structures. (...)

Yet the program construct, unlike the poet's words, is real in the sense that it moves and works, producing visible outputs separately from the construct itself. It prints results, draws pictures, produces sounds, moves arms. The magic of myth and legend has come true in our time. One types the correct incantation on a keyboard, and a display screen comes to life, showing things that never were nor could be.

Programming then is fun because it gratifies creative longings built deep within us and delights sensibilities we have in common with all men.

The Mythical Man-Month: Essays on Software Engineering by Frederick Brooks

2016-11-21T23:42:35
import logging

logging_config = {
    'filename': '/var/log/app_log',
    'format': '%(asctime)s [%(levelname)s] %(message)s',
    'level': logging.INFO
}
logging.basicConfig(**logging_config)

logging.info('Our logged message.')

This will output the following to /var/log/app_log:

2016-11-21 23:50:53,677 [INFO] Our logged message.

Source: https://docs.python.org/2/howto/logging.html#logging-basic-tutorial

2016-11-21T23:35:33

The Old Way

import os

os.system('find /home/user/documents -type f -iname "*.doc"')

The New, Recommended Way

import subprocess

subprocess.check_call([
    'find',
    '/home/user/documents',
    '-type', 'f',
    '-iname', '*.doc'
])

Bonus Tidbit

At this point, we can incorporate some nice exception handling:

import subprocess

try:
    subprocess.check_call([
        'find',
        '/home/user/documents',
        '-type', 'f',
        '-iname', '*.doc'
    ])
except subprocess.CallProcessError as e:
    print e.returncode
    print e.cmd
    print e.output

See the official Python Documentation for more usage and recommendations on the subprocess module.

2016-11-11T16:55:21
import json

polls = Poll.objects.all()

# Convert our QuerySet into a list so polls can be serialized
print json.dumps(list(p), indent=2)
JsonResponse({'polls': list(polls)})

Source: http://stackoverflow.com/questions/7650448/django-serialize-queryset-values-into-json

2016-11-03T20:05:28
import json
import psycopg2
from psycopg2.extras import RealDictCursor

cursor = conn.cursor(cursor_factory=RealDictCursor)
objects = cursor.fetchall()

print json.dumps(objects, indent=2)

# Django
#JsonResponse({'objects': objects})

Source: https://www.peterbe.com/plog/from-postgres-to-json-strings