Performing Binary Search in List - Python

Question

I'm working on an assignment for my computer class and I'm having a bit of trouble with a question. Question 1 and 2 kind of overlap, so I'll post both, and the code I have so far.

Question 1: Write a function called readCountries that reads a file and returns a list of countries. The countries should be read from this file, which contains an incomplete list of countries with their area and population. Each line in this file represents one country in the following format:

name, area(in km2), population

When opening the file your function should handle any exceptions that may occur. Your function should completely read in the file, and separate the data into a 2-dimensional list. You may need to split and strip the data as appropriate. Numbers should be converted to their correct types. Your function should return this list so that you can use it in the remaining questions.

This is my code for this part:

    def readCountries():
        countryList = []
        for line in open('Countries.py', 'r'):
            with open('Countries.py', 'r') as countriesFile:
                countries = countriesFile.read()
                countryList.append(line.strip().split())
        return countryList

Question 2: Write a function called getCountry that takes a string representing a country name as a parameter. First call your answer from question 1 to get the list of countries, then do a binary search through the list and print the country's information if found.

This is my code for this part:

    countryList = readCountries()

    def getCountry(countryList, name):
        lo, hi = 0, len(countryList) - 1
        while lo <= hi:
            mid = lo + (hi - lo) // 2
            country = countryList[mid]
            test_name = country[0]
            if name > test_name:
                lo = mid + 1
            elif name < test_name:
                hi = mid - 1
            else:
                return country
        return countries[lo] if countries[lo][0] == name else None

The output is this: ['Canada', '9976140.0', '35295770'] which is partially what I need, but how would I get it to look like this: Canada, Area: 9976140.0, Population: 35295770?

Answer 1

Well, one obvious problem is this line:

readCountries() 

should be like this:

countryList = readCountries() 

You got half way there by having the readCountries function return the list, but you never actually assign anything to what it's returning, so it just goes off into nowhere.