Getting mouse Locations in Coordenates

Hi you all, I am trying to get the mouse location in

    > coordenates, i have been able to get the X and Y position in
    > pixels however getting the location in coordinates has not
    > been possible. My code as follows:

    > self.figura = Figure(figsize=(8,4), facecolor=0.99, dpi=70,
    > frameon=True)
    > self.canvas = FigureCanvasGTK(self.figura)
    > self.canvas.connect("button_press_event", self.location)

You want matplotlib events, not gtk events

self.canvas.mpl_connect("button_press_event", self.location)