Creating a dictionary from csv file

Question

I was given the following problem and I am a little uncertain. I understand that the dictionary contains each town and their distance from each city, but is it structured like {Albury: 925,1440,352,3937,308,3583,565......} or something different?

The following table was downloaded from the web and saved in a file distances.csv. It specifies road distances, measured in kilometres, between major towns (eg Albury), and capital cities (eg Adelaide).

Town,Adelaide,Brisbane,Canberra,Darwin,Melbourne,Perth,Sydney
Albury,925,1440,352,3937,308,3583,565
Alice Springs,1544,2998,2658,1503,2255,3549,2931
Ballarat,618,1743,777,3645,112,3309,973
Bendigo,639,1619,653,3671,147,3335,849
Broken Hill,515,1545,1108,3128,825,2824,1154
Broome,4269,4646,4975,1880,4996,2233,5112
Cairns,3384,1699,2954,2885,3055,6050,2685
...

Consider the following code, which loads the data from this file.

from csv import DictReader
def p(f):
    a = {}
    for row in DictReader(open(f)):
        x = row["Town"]
        b = {}
        for k in row:
            if k != "Town":
                 b[k] = int(row[k])
        a[x] = b
    return a

t = p("distances.csv")

Briefly explain, in 20-30 words, the data structure contained in the variable t after the code has been executed.

Answer 1

If you add

import pprint
pprint.pprint(t)

at the bottom of the script and execute it, you will see your data structure quite clearly. It will look something like this:

{'Albury': {'Adelaide': 925,
            'Brisbane': 1440,
            (...)
            'Sydney': 565},
 'Alice Springs': {'Adelaide': 1544,
                   (...)

But, as @sarnold said in his comment, since this smells like homework, I'll leave it to you to explain the data structure. As a hint you might want to look at the DictReader documentation for how the data is created.