Goal:
  
  ============================
   (∀ (A : Type) (P : A → A → Type) (a
                                     b : sigma
                                           (λ index : 
                                               sigma 
                                                 (λ _ : list A, list A),
                                              OnOne2 P 
                                                (pr1 index) 
                                                (pr2 index))) 
      (e : a = b),
      noConfusion_OnOne2_obligation_1 A P a b
        (noConfusion_OnOne2_obligation_2 A P a b e) = e)


DEBUG:Going to execute:
intros