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Python, Returning object class names by a function

I'm new to Python and this is my first question here. Hope any of you guys will be able to help me out.
I'm trying to call values inside an object from an external program. The object that I'm trying to access is given in a class (as i uderstand it), and the name of the class may change according to X, see below:
External programs object and class information
I want to be able to call information from Phase_6 in this case, however it could be Phase_12 in another case. I was considering making a function where i could have the _'Number' as an input. But I can't seem to find any information of how to do such.
I was thinking of something like using +str(X), as I do when plotting. But as it is probably not a string, it doesn't work out.
My proposed code
Ive read that bpy in Blender may be able to replace the name of the class that i want to return, however I'm not sure if it'll work, and I dont want to switch editor :)
Hope you guys can help me out,
Joachim

Found the answer, one could use getattr.
x = 6
result = getattr(g_o, 'phase_'+str(x)).Info.SumMsf.value
Thanks anyway - And I'll work on the pictures
Joachim

How to add a track to an iTunes playlist using Python and Scripting Bridge

I learned how to create a playlist in a previous question, but now I can't figure out how to add tracks to it. Right now I have:
tracks.sort(key=lambda tup: tup[0])
i = 0
for trackList in generatePlaylists(tracks,10):
i += 1
playlistname = str(i)
p = {'name': playlistname}
playlist = iTunes.classForScriptingClass_("playlist").alloc().initWithProperties_(p)
iTunes.sources()[0].playlists().insertObject_atIndex_(playlist, 0)
# Find the playlist I just made
for playlist in iTunes.sources()[0].playlists():
if playlist.name() == playlistname:
newPlaylist = playlist
# Add the tracks to it
for track in trackList:
print track[1].name()
iTunes.add_to_(track[1],newPlaylist)
My tracks are in a list of tuples tracks, where the first element of the tuple is a score and the second is the actual track object. generatePlaylists is an iterator which splits all library tracks into 10 lists.
The above code runs without error, but in iTunes the playlists are empty.

First, here's the short answer:
track.duplicateTo_(newPlaylist)
The problem is that iTunes.add_to_ sends the add command, which takes a file (alias) and imports it into a playlist; you want to send the duplicate command, which takes any object and makes another copy of the object. You don't have a file, you have a track. (You could get a file via track.location(), but you don't want to re-import the file, just copy the track over.)
Also, in this case, you need to call the method on the track, rather than calling it on the app and passing it the track.
The first half of this is hard to explain without a solid understanding of the iTunes object model (and the AE model underneath it). But you don't really need to understand it. In most cases, by looking over the iTunes scripting dictionary (in AppleScript Editor) and trial and error (in AppleScript Editor or with py-appscript) you can figure it out what you want. (Just make sure you're working on a scrap library, or have a backup…) In this case, the only commands it could possibly be are add, copy, duplicate, or move, so just try them all and see what they do. Or, alternatively, go to dougscripts and download a bunch of samples and find one that does what you want.
The second half of this, figuring out how to translate to ScriptingBridge… well, I can't explain it without going into a long rant on SB (which hhas does much better than me, if you want to read one). But the basics are this: As far as iTunes is concerned, duplicate is a command. If you give it a direct object (tell application "iTunes" to duplicate theTrack to thePlaylist) it'll use that; if not, you're asking the subject to duplicate itself (tell theTrack to duplicate to thePlaylist). It works exactly like English. But SB insists on an object-oriented model, where duplicate is a method on some object. So, only one of those two forms is going to work. In general, you can figure out which by just looking at dir(iTunes) and dir(track) to see which one has a method that looks like the command you want.
As you can tell from the above, you've got a lot of trial and error ahead of you if you're trying to do anything complicated. Good luck, and keep asking.
PS, I have no idea why your code fails silently. The obvious way the add_to_ method should translate into a command should raise a -1708 error (as appscript iTunes.add(track, to=newPlaylist) or AppleScript add theTrack to newPlaylist both do…).

Python and XPath

I'm trying to parse this XML
I want to get a list of all of the mechanisms, so I'm trying to use XPATH (please suggest if theres an easier way) to get the mechanisms...
Here is my code:
parseMessage = libxml2.parseDoc(doc)
xpathcon = parseMessage.xpathNewContext()
xpathcon.xpathRegisterNs('urn','http://etherx.jabber.org/streams')
nodes = xpathcon.xpathEval("//urn:text()")
print nodes
And here is the error I'm getting...
Entity: line 1: parser error : Premature end of data in tag stream line 1
h"/><register xmlns="http://jabber.org/features/iq-register"/></stream:features>
I know that my code doesn't remove all the mechanisms but first I'd just like to get around the issue at hand. Anyway to make this into correct XML that can be parsed? Do I need to add a new header or remove a header or do something else?

It looks like you're trying to build an XMPP library. Why not use an existing library, such as SleekXMPP?
If you really need to build your own XMPP library, you'll need to use a streaming parser, such as Expat.

Please use one of the existing XMPP libraries.
Next: you're not going to be successful with XMPP thinking of it like a document. You'll be able to hack around it for a few days making yourself believe that you're on to something, and then you'll realize that there is no way to tell when the server is done sending you information, so there's no way to know when to call what you have a document.
Instead, use a stream-based parser. SleekXMPP uses xml.etree.cElementTree.iterparse with a wrapper around the socket to make it smell like a file. There are likely other ways, like using xml.parsers.expat directly.

Is it possible to inject shell/python commands from a configuration file?

Say you have a some meta data for a custom file format that your python app reads. Something like a csv with variables that can change as the file is manipulated:
var1,data1
var2,data2
var3,data3
So if the user can manipulate this meta data, do you have to worry about someone crafting a malformed meta data file that will allow some arbitrary code execution? The only thing I can imagine if you you made the poor choice to make var1 be a shell command that you execute with os.sys(data1) in your own code somewhere. Also, if this were C then you would have to worry about buffers being blown, but I don't think you have to worry about that with python. If your reading in that data as a string is it possible to somehow escape the string "\n os.sys('rm -r /'), this SQL like example totally wont work, but is there similar that is possible?

If you are doing what you say there (plain text, just reading and parsing a simple format), you will be safe. As you indicate, Python is generally safe from the more mundane memory corruption errors that C developers can create if they are not careful. The SQL injection scenario you note is not a concern when simply reading in files in python.
However, if you are concerned about security, which it seems you are (interjection: good for you! A good programmer should be lazy and paranoid), here are some things to consider:
Validate all input. Make sure that each piece of data you read is of the expected size, type, range, etc. Error early, and don't propagate tainted variables elsewhere in your code.
Do you know the expected names of the vars, or at least their format? Make sure the validate that it is the kind of thing you expect before you use it. If it should be just letters, confirm that with a regex or similar.
Do you know the expected range or format of the data? If you're expecting a number, make sure it's a number before you use it. If it's supposed to be a short string, verify the length; you get the idea.
What if you get characters or bytes you don't expect? What if someone throws unicode at you?
If any of these are paths, make sure you canonicalize and know that the path points to an acceptable location before you read or write.
Some specific things not to do:
os.system(attackerControlledString)
eval(attackerControlledString)
__import__(attackerControlledString)
pickle/unpickle attacker controlled content (here's why)
Also, rather than rolling your own config file format, consider ConfigParser or something like JSON. A well understood format (and libraries) helps you get a leg up on proper validation.
OWASP would be my normal go-to for providing a "further reading" link, but their Input Validation page needs help. In lieu, this looks like a reasonably pragmatic read: "Secure Programmer: Validating Input". A slightly dated but more python specific one is "Dealing with User Input in Python"

Depends entirely on the way the file is processed, but generally this should be safe. In Python, you have to put in some effort if you want to treat text as code and execute it.

Need example/help with GtkTextBuffer (of GtkTextView) serialize/deserialize

I am trying to save user's bold/italic/font/etc tags in a GtkTextView.
Using GtkTextBuffer.get_text() does not return the tags.
The best documentation I have found on this is:
http://www.pygtk.org/docs/pygtk/class-gtktextbuffer.html#method-gtktextbuffer--register-serialize-format
However, I do not understand the function arguments.
It would be infinitely handy to have an example of how these are used to save/load a textview with tags in it.
Edit: I would like to clarify what I am trying to accomplish. Basically I want to save/load the textview's text+tags. I have no desire to do anything more complicated than that. I am using pickle as the file format, so I dont need any help here on how to save it or in what format. Just need a way to pull/push the data so that the user loses nothing that he/she sees on screen. Thank you.

If you need to save the tags because you just want to copy the text into another text buffer, you can use gtk.TextBuffer.insert_range().
If you need to save the text with tags into another format readable by other programs, I once wrote a library with a GTK text buffer serializer to and from RTF. It doesn't have any Python bindings though. But in any case the code is a good example of how to use the serializer facility. Link: Osxcart

I haven't worked with GtkTextBuffer's serialization. Reading the documentation you linked, I would suggest trying the default serializer, by calling
textbuffer.register_serialize_tagset()
This gives you GTK+'s built-in proprietary serializer. Being proprietary here means that it doesn't serialize into some well-known format; but if all you need is the ability to save out the text buffer's contents and load them back, this should be fine.
Of course the source code is available inside GTK+ if you really want to figure out how it works; I would recommend against trying to implement e.g. a stand-alone de-serializer though, since there are probably no guarantees made by GTK+ that the format will remain as-is.