What is the series code for number of infant deaths in year 1965 for the country whose full name is Islamic State of Afghanistan?
number of infant deaths refers to IndicatorName = 'Number of infant deaths'; in year 1965 refers to Year = '1965'; full name is Islamic State of Afghanistan refers to LongName = 'Islamic State of Afghanistan'
SELECT DISTINCT T3.Seriescode FROM Country AS T1 INNER JOIN Indicators AS T2 ON T1.CountryCode = T2.CountryCode INNER JOIN CountryNotes AS T3 ON T2.CountryCode = T3.Countrycode WHERE T2.IndicatorName = 'Number of infant deaths' AND T1.LongName = 'Islamic State of Afghanistan' AND T2.Year = 1965