fact: Definition v_inv0 (C1 C2 : Type) : C1 × C2 -> C1 * C2.
imports: mathcomp(all_ssreflect all_algebra boolp distr reals realsum) Mon(SpecificationMonads SPropBase SPropMonadicStructures) Relational(OrderEnrichedCategory OrderEnrichedRelativeMonadExamples) Crypt(ChoiceAsOrd SubDistr Couplings Axioms)