Doc: https://docs.python.org/3/library/csv.html

names.csv

first_name,last_name,email
John,Doe,john.doe@mail.com
Mary,Smith,mary.smith@mail.com
Jane,Stuart,jane.stuart@mail.com

import csv
 
with open("names.csv", "r") as csv_file:
    csv_reader = csv.reader(csv_file)
 
    for line in csv_reader:
        first_name = line[0]
        last_name  = line[1]
        email      = line[2]

Chaque ligne est une liste de valeurs.

La première ligne contient les noms des colonnes.

Si le délimiteur n'est pas spécifié, c'est par défaut la virgule.

On peut spécifier un autre délimiteur dans le constructeur :

    csv_reader = csv.reader(csv_file, delimiter="\t")
    csv_reader = csv.reader(csv_file, delimiter=";")

import csv
 
with open("names.csv", "w") as csv_file:
    csv_writer = csv.writer(csv_file, delimiter=";")
 
    csv_writer.writerow(["Steve", "Rogers", "steve.rogers@mail.com"])

import csv
 
with open("names.csv", "r") as csv_file:
    csv_reader = csv.DictReader(csv_file)
 
    for line in csv_reader:
        first_name = line["first_name"]
        last_name  = line["last_name"]
        email      = line["email"]

import csv
 
with open("names.csv", "w") as csv_file:
 
    fieldnames = ["first_name", "last_name"]
    csv_writer = csv.DictWriter(csv_file, fieldnames=fieldnames, delimiter="\t")
 
    csv_writer.writeheader()
    csv_writer.writerow({"first_name": "Neil", "last_name": "Jenkins"})
    csv_writer.writerow({"first_name": "Tom",  "last_name": "Jefferson"})
    csv_writer.writerow({"first_name": "Sam",  "last_name": "Smith"})