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How to create a dynamic form with python using translated text as input?

I have an original text that I want to translate. I normally do it manually but I know I could save a lot of time translating automatically the most frequent words and expressions.
I will find out how to translate simple words, the problem is not here. I have read some books on python and I think using string manipulations can be done.
But I am lost about how to create the output file.
The output file will contain:
short empty forms ready to be filled wherever there is text that has not been translated
the translated words wherever they were in the original file
In the output file I will fill manually the empty forms, after pressing Tab the cursor should jump to the next exmpty form
I am lost here, I know how to do forms on html but the language I am used to is Python.
I would like to know what modules from Python I could use. I need some guidance on this.
Can you recommend me a book or a tool that explains how to do something similar to this?
This is what I want to do, assuming I have managed to create a simple database to translate colors from Spanish to English.
The first step contains the original file.
The second step contains the automatic translation.
In the third step I complete the manual translation.
After finishing everything is grouped into a normal txt file ready to be used.
I think it is quite clear. I don't expect people to tell me the code to do this, I just need to know what tools could be used to achieve my goal.
Thanks for editing.

To create an interface that works with a web browser, Flask for Python is a good method for creating webforms. There are tutorials available.
One method for storing data would be an SQLite file. That may be more than you need, so I'd recommend starting with a CSV file. Libraries exist in Python for both CSVs and SQLite.

Execute python functions and read variables from html

First off, I am very new to programming and I have a relatively basic understanding of python, and average understanding of html.
Using what I know in python, I am trying to create a basic strategy game, a bit like the likes of Age of Empires, or Command and Conquer, based on collecting resources and using it to build things, except using a simple text or button-clicking type interface. I can do a text interface fine, but its a bit boring, and I would like to use some images. I have had a 1 hour lecture on tkinter, but I have tried and failed to make anything remotely 'usable' from it. What I can do, is make decent looking html pages which would serve my purpose very well.
What I am wondering is if there is a simple way of executing python functions and calling/displaying python variables through a html page? The python functions do all the logic and present variables which represent current resource levels, production, storage capability, levels of buildings, etc. At the most basic level all I need is a way of displaying these variables, and having buttons which execute a function to say, upgrade a building, which recalculates production and all that, and returns the new set of values.
As a really simple example:
<p> Wheat production: *python integer representing production*</p>
<button type="button" onclick="*execute python variable*">Upgrade Wheat</button>
There would also, I imagine, be a need to somehow update the variables which are changed on the html page. So the button executes a function to upgrade wheat production, python now has a new value for the wheat production variable, and this needs to be updated on the page, whether this is automatic, or by some other method. I guess the simple way would be if pressing the button could also reload the page, but that seems a little clumsy.
Does anyone know of a simple way of doing this? Or perhaps a python library which might help me here?

Yes, there is a way of doing this.
There are two approaches to this. One is to have all the work done on the server, the other approach is to use Javascript.
The first approach is this: write a python script that generates your HTML. If you use Django, you will get a lot of work done for you, but you will also get a lot of stuff you don't want. Django does have a built-in template language. Django is beyond the scope of this answer. You will get to do exactly what you describe above; an example of a template might be <p> Wheat production: {{wheat_production}}</p> - your python code will set up a dict mydict={"wheat_production":10} and you will pass the name of your template file and the dict to a function which will spit out your page. You will also have to learn about HTML forms, if you haven't done so yet.
The other approach is to use Ajax - Javascript that, when your page is displayed (and, perhaps, when buttons are clicked, or at regular intervals) will send/receive some data to allow you to update your page. I suggest looking into JQuery to do some of the lifting for you. This means that you can update bits of the page without having to reload the entire thing. You will still have to write some code on the server to talk to the database, and send the output, usually as JSON, back to the client.
When writing this sort of thing, make sure all of your security is on the server side, and don't trust anything the user tells you. For example, if you store the number of gold pieces in a field on your form, it's going to take someone about 10 seconds to give themselves as much gold as they want. Similarly, if a player can sell a diamond for 20 gold pieces, make sure they have the diamond before giving them the gold pieces - you don't want to end up with a player with 1,000,000 gold pieces and negative a thousand diamonds. Javascript is 100% insecure, anything that Javascript can do, the player can also do.

Take a look at http://pyjs.org/
What is pyjs?
pyjs is a Rich Internet Application (RIA) Development Platform for
both Web and Desktop. With pyjs you can write your JavaScript-powered
web applications entirely in Python.
pyjs contains a Python-to-JavaScript compiler, an AJAX framework and a
Widget Set API. pyjs started life as a Python port of Google Web
Toolkit, the Java-to-JavaScript compiler.
You can compile Python programs to javascript, and also use their Python libraries to generate HTML. Here's an example from their getting started guide:
from pyjamas import Window
from pyjamas.ui import RootPanel, Button
def greet(sender):
Window.alert("Hello, AJAX!")
class Hello:
def onModuleLoad(self):
b = Button("Click me", greet)
RootPanel().add(b)

Create a 'single-serving site' with python

I want to make a Python script available as a service on the net. The script, which is my first 'proper' Python program, takes a txt file as argument and writes an image into the work directory. So:
How difficult is it for somebody who is new to Python and web development?
How much work is it?
Do I need a framework (Django, cherryPy, web2py)?
Are there good tutorials?
How do I avoid the server to be compromised?
What are my next steps?
==> What is the easiest way?
In the end it is enough, if it is a white page, with some text, and a button, which when clicked, opens a file dialog. After the txt is processed, the server should just return the image, which was written on the hard drive. Already I have access to a server which has Ubuntu installed through a friend.
[update]
Thanks for all your answers. After reading them I want to stress again, that I want to have it as minimal as possible. Srikar's suggestion sounds like the easiest one:
Put it in executable directory of your OS (commonly known as CGI
path). Provide a simple HTML form & upon form submission hit this
script which executes & returns back the image you want to display.
Any objections or comments? Do you know any tutorials for that?
[udpate2]
I found this SO answer: File Sharing Site in Python Is this a sensible approach?

It's not too difficult. Actually, it sounds like a good first project.
That too subjective to answer. An hour to days.
No, you don't need one, but I'd use one if I were you. They abstract away some of the stuff you really don't care about, and you'll learn a tool you can use again in the future.
Plenty. If you want a real rundown of how Python works for the web, read the HOWTO from Python.org. If you just want to learn how to do this one project, pick a framework and do their tutorial.
This question is so broad and complex that I'm not going to try to answer it. Search this site, or Google, for questions like that.
Your next step should be to pick a framework; I've used Django successfully. Just download it, follow the installation instructions, and work your way through their tutorial; it should tell you everything you need to know to do what you want. If you still have questions once you've learned how to do the basics, come back and ask again!
Edit: The answer to that other question will certainly work for you. There, they just receive a GET request and respond with data from a Python file. You need to receive a GET request, respond with an HTML page (easy enough), then respond to a POST request that includes an uploaded file (slightly more complicated) and run your python routine on the uploaded file and then respond with the created image (or a link to it).
Take a look at this page which includes a simple Python script to do file uploads. You should easily be able to modify it to do what you want.

How difficult is it for somebody who is new to Python and web development?
Depends on your level of knowledge.
How much work is it?
Depends on which method you choose to solve the problem.
Do I need a framework (Django, cherryPy, web2py)?
Not necessarily - you could get started by using the CGI (http://docs.python.org/library/cgi.html)
Are there good tutorials?
Yes, there are plenty. The Python docs are an excellent place to start.
How do I avoid the server to be compromised?
Again, depends on the method you choose to solve the problem, although there are commonalities.
What are my next steps?
Dare I say it again, choose a method, read the docs, have a play!

If its just as simple as you have described it. Then you might not even need Django. You could simply use CGI scripting. All of these design decisions, depend on whether
You need (or foresee) a SQL storage?
or a Content-Management-System?
Will you need multiple-user support?
Do you need tight security?
Do you need different privileges for different users?
Do you need an Admin to manage your site?
If the answer to above questions is atleast 60% correct, then you might consider Django. otherwise, just write a python script. Put it in executable directory of your OS (commonly known as CGI path). Provide a simple HTML form & upon form submission hit this script which executes & returns back the image you want to display. So, it all depends on the features you need...

In the end, I created what I needed with Flask.
They have a well documented pattern / tutorial on Uploading Files. The tutorial is understandable even for people with little python and web expericence.
To get a first working version it took me 2h and the resulting code was only 50 lines. This includes, starting the webserver, having a html file/form with file upload and serving a file back to the user.

How to create an internationalized Google App Engine application

I would like to provide my Python GAE website in the user's own language, using only the tools available directly in App Engine. For that, I would like to use GNU gettext files (.po and .mo files).
Has someone successfully combined Python Google App Engine and gettext files? If so, could you please provide the steps you used?
I had started a discussion in GAE's Google group, but haven't been able to extract from it how I'd like to do it: I don't want to add external dependencies, like Babel (suggested in the discussion). I want to use plain vanilla Google App Engine, so no manual update of Django or this kind of stuff.
At first, I will start using the language sent by the browser, so no need to manually force the language by using cookies etc. However, I might add a language changing feature later, once the basic internationalization works.
As a background note to give you more details about what I'm trying to do, I would like to internationalize Issue Tracker Tracker, an open source application I've hosted on Launchpad. I plan to use Launchpad's translation platform (explaining why I'd like to use .mo files). You can have a look at the source code in it's Bazaar branch (sorry no link due to stackoverflow spam prevention limit for new users...)
Thanks for helping me advance on this project!

As my needs were simple, I used a simple hack instead of (unavailable) gettext. I created a file with string translations, translate.py. Approximately like this:
en={}
ru={}
en['default_site_title']=u"Site title in English"
ru['default_site_title']=u"Название сайта по-русски"
Then in the main code I defined a function which returns a dictionary with translations into the most suitable language from the list (the first one to have a translation is used or English):
import translate
def get_messages(languages=[]):
msgs=translate.en
for lang in languages:
if hasattr(translate,lang):
msgs=getattr(translate,lang)
break
return msgs
Usage:
msgs = get_messages(["it","ru","en"])
hi = msgs['hello_message'] % 'yourname'
I also defined a helper function which extracts a list of languages from Accept-Language header.
It's not the most flexible solution, but it doesn't have any external dependencies and works for me (in a toy project). I think translate.py may be generated automatically from gettext files.
In case you want to see more, my actual source is here.

You can use the Django internationalisation tool, like explained here.
They are also saying that there is no easy way to do this.
I hope that helps you :)

Django missing translation of some strings. Any idea why?

I have a medium sized Django project, (running on AppEngine if it makes any difference), and have all the strings living in .po files like they should.
I'm seeing strange behavior where certain strings just don't translate. They show up in the .po file when I run make_messages, with the correct file locations marked where my {% trans %} tags are. The translations are in place and look correct compared to other strings on either side of them. But when I display the page in question, about 1/4 of the strings simply don't translate.
Digging into the relevant generated .mo file, I don't see either the msgid or the msgstr present.
Has anybody seen anything similar to this? Any idea what might be happening?
trans tags look correct
.po files look correct
no errors during compile_messages

Ugh. Django, you're killing me.
Here's what was happening:
http://blog.e-shell.org/124
For some reason only Django knows, it decided to decorate some of my translations with the comment '# fuzzy'. It seems to have chosen which ones to mark randomly.
Anyway, #fuzzy means this: "don't translate this, even though here's the translation:"
I'll leave this here in case some other poor soul comes across it in the future.

The fuzzy marker is added to the .po file by makemessages. When you have a new string (with no translations), it looks for similar strings, and includes them as the translation, with the fuzzy marker. This means, this is a crude match, so don't display it to the user, but it could be a good start for the human translator.
It isn't a Django behavior, it comes from the gettext facility.