Reading multiple lines from another file into a tuple - python-3.x

Question

I can't seem to pull each individual line from a .txt file into a tuple. The 'city-data.txt' file is just a list of the 50 states, capitols, and their lat/longs. I need to create a tuple of all the states.
This is my code so far -
def read_cities(file_name):
file_name = open('city-data.txt' , 'r')
for line in file_name:
road_map = ((line.split('\t')))
return road_map
file_name.close()
print(read_cities('city-data.txt'))
When it's run, it only prints the very first line from the .txt file, as such:
['Alabama', 'Montgomery', '32.361538', '-86.279118\n']

Answer 1

The reason it prints only the very first line is because of this
for line in file_name:
road_map = ((line.split('\t')))
return road_map
You are returning immediately after you consume the first line. This is why it only prints the very first line.
Instead, you need to store these in a list, and return that list in the end.
def read_cities(file_name):
file_name = open('city-data.txt' , 'r')
road_maps = []
for line in file_name:
road_map = ((line.split('\t')))
road_maps.append(road_map)
file_name.close()
# road_maps is a list, since you wanted a tuple we convert it to that
return tuple(road_maps)
print(read_cities('city-data.txt'))
I need to create a tuple of all the states.
Does this mean you only want the first column from each line ? If so, modify it to
def read_cities(file_name):
# notice I've changed this to use file_name instead of
# the hard-coded filename string
file_name = open(file_name , 'r')
# if you need uniqueness, use states=set() and use .add instead
# of .append
states = []
for line in file_name:
line_split = line.split('\t')
# line_split is a list and the 0th index is the state column
state = line_split[0]
# use states.add if you used a set instead of a list
states.append(state)
file_name.close()
return tuple(states)
print(read_cities('city-data.txt'))