(self)
RI - Executes a reverse line feed: Move the cursor up one line to the
        home position.  If the cursor move would result in going past the top
        margin of the screen (upwards) this will execute a scroll_down() event.
RI - Executes a reverse line feed: Move the cursor up one line to the
        home position.  If the cursor move would result in going past the top
        margin of the screen (upwards) this will execute a scroll_down() event.
RI - Executes a reverse line feed : Move the cursor up one line to the home position . If the cursor move would result in going past the top margin of the screen ( upwards ) this will execute a scroll_down () event .
def reverse_linefeed(self):
        """
        RI - Executes a reverse line feed: Move the cursor up one line to the
        home position.  If the cursor move would result in going past the top
        margin of the screen (upwards) this will execute a scroll_down() event.
        """
        self.cursorX = 0
        self.cursorY -= 1
        if self.cursorY < self.top_margin:
            self.scroll_down()
            self.cursorY = self.top_margin
def reverse_linefeed ( self ) : self . cursorX = 0 self . cursorY -= 1 if self . cursorY < self . top_margin : self . scroll_down ( ) self . cursorY = self . top_margin