Understanding Python's With Statement

Turns out the 'with' statement in Python is fairly straight forward.  Here is an article (oldie but goodie) that gives a quick thumbnail sketch of how that statement works:

http://effbot.org/zone/python-with-statement.htm

On another note, this is the first blog of the New Year!

Parsing Excel with Python

Cos sometimes you don't want to deal with xml, csv, json or any other text format.  Check out https://openpyxl.readthedocs.org/en/latest/.

Design Patterns

I generally avoid buying computer books because they become outdated very quickly.  However, Design Patterns by Gamma, Helm, Johnson, and Vlissides is an exception (probably due to its general nature):

http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612/ref=sr_1_1?s=books&ie=UTF8&qid=1411492186&sr=1-1&keywords=design+patterns

 This book makes me rethink how I approach object oriented programming.

Setting the PYTHONPATH with the Powershell permanently

I actually got a lot of tips on how to do this through this article:

http://technet.microsoft.com/en-us/library/ff730964.aspx

If you have the .NET Framework, you can do the following:

> [Environment]::SetEnvironmentVariable("PYTHONPATH", "D:/mypath", "User")

In order to see the changes, you need to open a new Powershell.

Setting the PYTHONPATH with Powershell

Powershell is the Windows hacker's best friend until it isn't.  Actually, I really do enjoy the power you get from Powershell.  However, figuring out how to set my python path in the shell was a frustrating experience that I hope to spare other users from.

PS C:\Users\spearsc> Get-ChildItem Env:PYTHONPATH

Name                                    Value
----                                        -----
PYTHONPATH                     r:/env


PS C:\Users\spearsc> $env:PYTHONPATH = "D:/localenv"
PS C:\Users\spearsc> Get-ChildItem Env:PYTHONPATH

Name                           Value
----                               -----
PYTHONPATH           D:/localenv

There you have it!  Pretty sure this setting is not permanent, which is fine for testing purposes.

Dealing with the error message: "Cross origin requests are only supported for HTTP."

I know I have dealt with this before, but I found a Stack Overflow thread that does a pretty good job of explaining this problem.  Plus, the thread shows you how to use Python to fire up a simple web server to get around the issue:

http://stackoverflow.com/questions/20041656/xmlhttprequest-cannot-load-file-cross-origin-requests-are-only-supported-for-ht

Multiprocessing Versus Threading in Python

I keep forgetting the difference between multiprocessing and threading in Python.  This Stack Overflow thread explains the difference between the two pretty well:

http://stackoverflow.com/questions/3044580/multiprocessing-vs-threading-python