ValueError : not enough values to unpack. why?

问题:

I am learning file management from a website and I tried executing a certain script but it hasn't worked out well for me.

It keeps returning this error at the line : city, day, time = line.split()

ValueError: not enough values to unpack (expected at least 2, got 0)

I am trying to alphabetize and pickle dump a list of cities and their time zones, the text file has several lines such as this:

Salt lake city Sun 09:52
San Francisco Sun 00:52
Amsterdam Sun 08:52
Denver Sun 01:52
San Salvador Sun 01:52
Detroit Sun 02:52

This is the code:

import pickle

lines = open("cities_and_times.txt").readlines()
lines.sort()

cities = []
for line in lines:
    *city, day, time = line.split()
    hours, minutes = time.split(":")
    cities.append((" ".join(city), day, (int(hours), int(minutes)) ))

    f_new = open("cities_and_times.pkl", "bw")
    pickle.dump(cities, f_new)

    print(cities)

回答1:

You need an if condition which will allow you to skip over blank lines. Something like:

if not line:
   continue

# Or do this

if not line:
   pass
else:
   *city, day, time = line.split()