Question

Problem 9 - PYTHON

There is a CSV-formatted file called olympics2.csv. Write code that creates a dictionary named country_olympians where the keys are country names and the values are lists of unique olympians from that country (no olympian's name should appear more than once for a given country).

Name,Sex,Age,Team,Event,Medal
A Dijiang,M,24,China,Basketball,NA
A Lamusi,M,23,China,Judo,NA
Gunnar Nielsen Aaby,M,24,Denmark,Football,NA
Edgar Lindenau Aabye,M,34,Sweden,Tug-Of-War,Gold
Christine Jacoba Aaftink,F,21,Netherlands,Speed Skating,NA
Christine Jacoba Aaftink,F,21,Netherlands,Speed Skating,NA
Christine Jacoba Aaftink,F,25,Netherlands,Speed Skating,NA
Christine Jacoba Aaftink,F,25,Netherlands,Speed Skating,NA
Christine Jacoba Aaftink,F,27,Netherlands,Speed Skating,NA
Christine Jacoba Aaftink,F,27,Netherlands,Speed Skating,NA
Per Knut Aaland,M,31,United States,Cross Country Skiing,NA
Per Knut Aaland,M,31,United States,Cross Country Skiing,NA
Per Knut Aaland,M,31,United States,Cross Country Skiing,NA
Per Knut Aaland,M,31,United States,Cross Country Skiing,NA
Per Knut Aaland,M,33,United States,Cross Country Skiing,NA
Per Knut Aaland,M,33,United States,Cross Country Skiing,NA
Per Knut Aaland,M,33,United States,Cross Country Skiing,NA
Per Knut Aaland,M,33,United States,Cross Country Skiing,NA
John Aalberg,M,31,United States,Cross Country Skiing,NA
John Aalberg,M,31,United States,Cross Country Skiing,NA
John Aalberg,M,31,United States,Cross Country Skiing,NA
John Aalberg,M,31,United States,Cross Country Skiing,NA
John Aalberg,M,33,United States,Cross Country Skiing,NA
John Aalberg,M,33,United States,Cross Country Skiing,NA
John Aalberg,M,33,United States,Cross Country Skiing,NA
John Aalberg,M,33,United States,Cross Country Skiing,NA
"Cornelia ""Cor"" Aalten (-Strannood)",F,18,Netherlands,Athletics,NA
"Cornelia ""Cor"" Aalten (-Strannood)",F,18,Netherlands,Athletics,NA
Antti Sami Aalto,M,26,Finland,Ice Hockey,NA
"Einar Ferdinand ""Einari"" Aalto",M,26,Finland,Swimming,NA
Jorma Ilmari Aalto,M,22,Finland,Cross Country Skiing,NA
Jyri Tapani Aalto,M,31,Finland,Badminton,NA
Minna Maarit Aalto,F,30,Finland,Sailing,NA
Minna Maarit Aalto,F,34,Finland,Sailing,NA
Pirjo Hannele Aalto (Mattila-),F,32,Finland,Biathlon,NA
Arvo Ossian Aaltonen,M,22,Finland,Swimming,NA
Arvo Ossian Aaltonen,M,22,Finland,Swimming,NA
Arvo Ossian Aaltonen,M,30,Finland,Swimming,Bronze
Arvo Ossian Aaltonen,M,30,Finland,Swimming,Bronze
Arvo Ossian Aaltonen,M,34,Finland,Swimming,NA
Juhamatti Tapio Aaltonen,M,28,Finland,Ice Hockey,Bronze
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,Bronze
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,Gold
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,Gold
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,28,Finland,Gymnastics,Gold
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,Bronze
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Paavo Johannes Aaltonen,M,32,Finland,Gymnastics,NA
Timo Antero Aaltonen,M,31,Finland,Athletics,NA
Win Valdemar Aaltonen,M,54,Finland,Art Competitions,NA

Answer 1

• Below is the detailed implementation of the above problem in PYTHON with code and output shown.
• For better understading please read the comments mentioned in the code.
• Make sure to have the csv file in the same path as that of the python file, so that python can read the file in case of path not specified.
• CODE:

#import modules
import pandas as pd

#create dictionary of the csv file with key as column names and value as another dictionary with key as first column i.e, Name
#and value same as column under which this dictionary is created

d1=pd.read_csv('olympics2.csv', index_col=0).to_dict()
#so we want mapping of team i.e, country and name so we select the dictionary for name as key and country as value
d1=d1["Team"]
#create our desired dictionary
country_olympians={}
#for key, value pairs in d1
for k,v in d1.items():
#if this value i.e, country is present in our dictionary as a key then add the key i.e, name as a value to it
if v in country_olympians.keys():
country_olympians[v].append(k)
#otherwise create a key value pair with key as country as value as list of names.
else:
country_olympians[v]=[k]
#print our desired dictionary.
print(country_olympians)

• OUTPUT:

{'China': ['A Dijiang', 'A Lamusi'], 'Denmark': ['Gunnar Nielsen Aaby'], 'Sweden': ['Edgar Lindenau Aabye'], 'Netherlands': ['Christine Jacoba Aaftink', 'Cornelia "Cor" Aalten (-Strannood)'], 'United States': ['Per Knut Aaland', 'John Aalberg'], 'Finland': ['Antti Sami Aalto', 'Einar Ferdinand "Einari" Aalto', 'Jorma Ilmari Aalto', 'Jyri Tapani Aalto', 'Minna Maarit Aalto', 'Pirjo Hannele Aalto (Mattila-)', 'Arvo Ossian Aaltonen', 'Juhamatti Tapio Aaltonen', 'Paavo Johannes Aaltonen', 'Timo Antero Aaltonen', 'Win Valdemar Aaltonen']}

• Below are the screenshot attached for the code and input/output for better clarity and understanding.

CODE and OUTPUT

So if you still have any doubt regarding this solution please feel free to ask it in the comment section below and if it is helpful then please upvote this solution, THANK YOU.