How many white patients whose birth year is 1935 have a stroke?
white refers to race = 'white'; birth year is 1935 refers to substr(birthdate, 1, 4) = '1935'; stroke refers to conditions.DESCRIPTION = 'Stroke';
SELECT COUNT(DISTINCT T1.patient) FROM patients AS T1 INNER JOIN conditions AS T2 ON T1.patient = T2.patient WHERE strftime('%Y', T1.birthdate) = '1935' AND T1.race = 'white' AND T2.DESCRIPTION = 'Stroke'