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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 image_corner(self, corner):
 """Return image corner in pixels, as shapely.Point."""

        if corner not in self.corner_types():
            raise GeoRaster2Error('corner %s invalid, expected: %s' % (corner, self.corner_types()))

        x = 0 if corner[1] == 'l' else self.width
        y = 0 if corner[0] == 'u' else self.height
        return Point(x, y)