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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 get_rendition_size(self, width=0, height=0):
        '''returns real rendition URL'''
        if width == 0 and height == 0:
            return (self.master_width, self.master_height)

        target_width = int(width)
        target_height = int(height)

        ratio = self.master_width / float(self.master_height)
        if target_height == 0 and target_width != 0:
            target_height = int(target_width / ratio)

        if target_height != 0 and target_width == 0:
            target_width = int(target_height * ratio)

        return target_width, target_height