How can I call the Ubuntu One authentication python script from a button using Glade?
what I need to do is call a python script such as: $ python u1file.py login
Gtk is a UI toolkit that is meant to be an event-driven framework. So the best approach would be to wait for some event to happen to execute your python code.
On Glade you can add widgets to a GtkWindow (that is also a widget), and widgets do emit what is called signals. Signals are events that indicate that something has happened. This action can be the user clicked on a button, typed some text, resized the window, etc.
A very simple example can be found here 
And here is a part I extracted
In the properties section, head to the signals tab having previously seleted some widget on the editor, for example a button.
As you can see in the image above, every signal has a name and can be binded to a "handler". Inside your code you have to create a function with the same name you choosed as your handle, in this case "on_window_destroy"
Then your code should look similar to this:
Import the script like you would do with any other module/package in Python.
See Hernantz answer if you don't know how to connect to a button.
Would this do what you want? This is basically the equivalent of typing