End Exports.
End Exports.
End Injection.
Export Injection.Exports.
Module InjectExtra.

Lemma inject_frame U W this s1 s2 s:
valid (U \+ W) ->
s1 \+ s \In Coh (U \+ W) ->
network_step U this s1 s2 ->
network_step (U \+ W) this (s1 \+ s) (s2 \+ s).