Extradition — Capital offences — Offence carrying death penalty in requesting State but not in requested State — Protocol VI to the European Convention on Human Rights, 1950 — Effect — Whether application of death penalty to extradited persons now contrary to French public policy — Obligation of requested State to seek assurance that death penalty will not be imposed or carried out — Whether unilateral condition laid down by requested State in granting extradition is sufficient — The law of France