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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def checkCursor(self):
        'override Sheet.checkCursor'
        if self.cursorBox:
            if self.cursorBox.h < self.canvasCharHeight:
                self.cursorBox.h = self.canvasCharHeight*3/4
            if self.cursorBox.w < self.canvasCharWidth:
                self.cursorBox.w = self.canvasCharWidth*3/4

        return False