JOHANNESBURG (Reuters) - Botswana's central bank left its benchmark lending rate unchanged at 7.5 percent for the third straight meeting on Tuesday, citing a positive medium-term economic outlook. "The current state of the economy, domestic and external economic outlook and the inflation forecast, suggest that the current monetary policy stance is consistent with maintaining inflation within the Bank's 3–6 percent objective in the medium term," the Bank of Botswana said.