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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 unbind(self):
 """Unbind the FBO."""

        # Unbind the FBO
        if self.texture.mipmap:
            with self.texture:
                self.texture.generate_mipmap()

        gl.glBindFramebufferEXT(gl.GL_FRAMEBUFFER_EXT, 0)

        # Restore the old viewport size
        gl.glViewport(*self._old_viewport)