 Complete the following phrase:  On 11 December 1953, during Juan Domingo Peróns second term, the vessels keel was laid down at the Río Santiago Shipyard, A.F.N.E. State Shipbuilding and Naval Factories, itself a peronist creation. Between 1954 and 1955 the shipyard engineers included several modifications to the vessels original design and configuration. During the de facto government of the self called 