Definition Lens reparametrization [efr-000L]

As in the definition of chart reparametrization, let A_1,A_2,B_1,B_2 be arenas, and let S_1, f_1: TS_1 \otimes A_1 \leftrightarrows B_1, S_2, f_2: TS_2 \otimes A_2 \leftrightarrows B_2 be controlled processes. Let

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