Assume H.
Apply H to the current goal.
Let F0 be given.
Assume H.
Apply H to the current goal.
Let F1 be given.
Assume H.
Apply H to the current goal.
Let eta be given.
Assume H.
Apply H to the current goal.
Let eps be given.
Let Init be given.
Assume H.
Apply H to the current goal.
Let uniq be given.
We use F0 Init to witness the existential quantifier.
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