python while true try except_Python为true时，Try/Except，返回valu

当我在生成一个变量并将while设置为True、try/except命令后尝试返回值时，该变量不返回该值。我正在努力使这个“起点”全球化，以便可以使用它。在def start_time():

while True:

try:

starting = int(input("Please enter a starting hour(HH): "))

if starting < 0:

print("There are no negative hours!")

elif starting > 24:

print("There are only 24 hours in a day!")

else:

break

except ValueError:

print("Please enter in a correct format (HH)")

return starting

def end_time():

while True:

try:

ending = int(input("Please enter an ending hour (HH): "))

if ending < starting:

print("You can only plan a day!")

elif ending < 0:

print("There are only 24 hours in a day!")

elif ending > 24:

print("There are only 24 hours in a day!")

else:

break

except ValueError:

print("Please enter in a correct format (HH)")

return ending

#obtain starting and ending time

start_time()

end_time()

#confirm starting and ending time

谢谢