please help me fix this buy proposal

divinely

how can some please help me correct this. i want to place i digit differ trade where last digit in one tick differs from 9. please help me out

proposal = await api.proposal({"proposal": 1, "amount": 10, "barrier": "9", "basis": "stake",
                               "contract_type": "DIGITS", "currency": "USD", "duration": 1, "duration_unit": "t",
                               "symbol": "R_100"
})
print(proposal)