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When was J. Paul Getty's grandson kidnapped?
In Rome on July 10, 1973, 'Ndrangheta kidnappers abducted J. Paul Getty's 16-year-old grandson, John Paul Getty III, and demanded a $17 million payment for his safe return.

Question: What did the kidnappers want?
Self-contained rewrite: What did the kidnappers of J. Paul Getty's grandson, John Paul Getty III, want from J. Paul Getty?