gobject.connect

I am new to this mailing list. I am working on a program to perform data analysis in python. This program is based on a library already developped, that uses pygtk to create data-handling objects. 

This data object inherits from gobject.GObject, and defines a few signals "new-data-point".

I would like to connect this signal to a few functions, specifying the arguments of these functions. I have read the PyGTK webpage (http://www.pygtk.org/docs/pygobject/class-gobject.html#method-gobject--connect), which specifies that i just have to concatenate in the "connect" call the arguments: "object.connect("signal_name",handler,arg1,arg2,arg3)

I therefore have written: 

data.connect("new-data-point", handler,'text')

and defined the handler function as suggested: def handler(object,arg1,arg2,arg3)

However, when i do execute the "connect" function, i get the error message: 

"connect takes exactly 3 arguments (4 given). 

Could you tell me how i could then specify arguments for the functions to be called when the signal is given ? 

Bests,

Pierre