what wrong with this code pleas need help

Question

def affich():
while True:
ch=input("donner une chaine de caracter: ")
if ch[0] in ch[0].upper() and 5<=len(ch)<=20 :
break
return ch
def calcul(ch):
nb=0
for i in range(1,len(ch)):
if ch[i]in ["1","2","3","4","5","6","7","8","9"]:
nb=nb+1
return nb
affich()
print(calcul(ch))