'Automagically set width for column.'

def _auto_set_column_width(self, col, renderer):

    cells = [key for key in self._cells if (key[1] == col)]
    width = 0
    for cell in cells:
        c = self._cells[cell]
        width = max(c.get_required_width(renderer), width)
    for cell in cells:
        self._cells[cell].set_width(width)
