if (time.strftime("%H:%M") != '0:26') and  (time.strftime("%H:%M") != '0:30') and  (time.strftime("%H:%M") != '0:40') and  (time.strftime("%H:%M") != '10:00') and  (time.strftime("%H:%M") != '11:00') and  (time.strftime("%H:%M") != '12:00') and  (time.strftime("%H:%M") != '12:30') and  (time.strftime("%H:%M") != '14:00') and  (time.strftime("%H:%M") != '15:00') and  (time.strftime("%H:%M") != '15:30') and  (time.strftime("%H:%M") != '16:00') and  (time.strftime("%H:%M") != '16:30') and  (time.strftime("%H:%M") != '17:00') and  (time.strftime("%H:%M") != '17:30') and  (time.strftime("%H:%M") != '18:00') and  (time.strftime("%H:%M") != '19:00'):
time.sleep(60)
else:
     выполняемый код

times=['0:26', '0:30', ... '19:00']
if time.strftime("%H:%M") not in times:
    time.sleep(60)
else:
     выполняемый код