Apart from importing the Contact class, we will also import the ContactForm and ContactList widgets:

import csv
import tkinter as tk

from chapter5_01 import Contact
from chapter5_02 import ContactForm, ContactList

class App(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("CSV Contact list")
        self.list = ContactList(self, height=12)
        self.form = ContactForm(self)
        self.contacts = self.load_contacts()

        for contact in self.contacts:
            self.list.insert(contact)
        self.list.pack(side=tk.LEFT, padx=10, pady=10)
        self.form.pack(side=tk.LEFT, padx=10, pady=10)
        self.list.bind_doble_click(self.show_contact)

    def load_contacts(self):
        with open("contacts.csv", encoding="utf-8", newline="") as f:
            return [Contact(*r) for r in csv.reader(f)]

    def show_contact(self, index):
        contact = self.contacts[index]
        self.form.load_details(contact)

if __name__ == "__main__":
    app = App()
    app.mainloop()