By Marianna Parraga HOUSTON (Reuters) – A unit of Italian oil company Eni has been assigned two 1-million-barrel cargoes of Venezuelan diluted crude oil for November loading, according to a document from state-run PDVSA seen by Reuters on Monday. The cargoes mark the resumption of an oil-for-debt deal authorized by the U.S. government earlier this year as an exception to sanctions on Venezuela’s oil sector. PDVSA owes billions of dollars to partners in dozens of oil and gas joint ventures, which has prompted some foreign firms to leave the country empty-handed while others have resorted to Was…