try:
int(input())
print('Да')
except ValueError:
pass
try:
print(('Да','')[99<int(input())<1000])
except:
pass
try:
print(('','Да')[99<int(input())<1000])
except:
pass
или
s=input('x= ')
if len(s)==3:
print(('','Да')[s.isdigit()])