Let p and q be given.
Assume Hp Hq Hpq.
Apply Hp to the current goal.
Assume H.
Apply H to the current goal.
Apply Hq to the current goal.
Assume H.
Apply H to the current goal.
An exact proof term for the current goal is HpN.
An exact proof term for the current goal is HqN.
An exact proof term for the current goal is Hpq.
Apply Hqp p HpN L1 to the current goal.
rewrite the current goal using H1 (from left to right) at position 1.
An exact proof term for the current goal is H1p.
An exact proof term for the current goal is H1.
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