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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 add_transform_chain(self, tc):
 """Insert the GLSL snippets of a transform chain."""

        # Generate the transforms snippet.
        for t in tc.gpu_transforms:
            if isinstance(t, Clip):
                # Set the varying value in the vertex shader.
                self.insert_vert('v_temp_pos_tr = temp_pos_tr;')
                continue
            self.insert_vert(t.glsl('temp_pos_tr'))
        # Clipping.
        clip = tc.get('Clip')
        if clip:
            self.insert_frag(clip.glsl('v_temp_pos_tr'), 'before_transforms')