data_manager.py

from pprint import pprint
import requests

SHEETY_PRICES_ENDPOINT = YOUR SHEETY PRICES ENDPOINT URL


class DataManager:

    def __init__(self):
        self.destination_data = {}

    def get_destination_data(self):
        # 2. Use the Sheety API to GET all the data in that sheet and print it out.
        response = requests.get(url=SHEETY_PRICES_ENDPOINT)
        data = response.json()
        self.destination_data = data["prices"]
        # 3. Try importing pretty print and printing the data out again using pprint().
        # pprint(data)
        return self.destination_data


    # 6. In the DataManager Class make a PUT request and use the row id  from sheet_data
    # to update the Google Sheet with the IATA codes. (Do this using code).
    def update_destination_codes(self):
        for city in self.destination_data:
            new_data = {
                "price": {
                    "iataCode": city["iataCode"]
                }
            }
            response = requests.put(
                url=f"{SHEETY_PRICES_ENDPOINT}/{city['id']}",
                json=new_data
            )
            print(response.text)

flight_search.py

import requests

TEQUILA_ENDPOINT = "https://tequila-api.kiwi.com"
TEQUILA_API_KEY = YOUR FLIGHT SEARCH API KEY


class FlightSearch:

    def get_destination_code(self, city_name):
        location_endpoint = f"{TEQUILA_ENDPOINT}/locations/query"
        headers = {"apikey": TEQUILA_API_KEY}
        query = {"term": city_name, "location_types": "city"}
        response = requests.get(url=location_endpoint, headers=headers, params=query)
        results = response.json()["locations"]
        code = results[0]["code"]
        return code

main.py

# 4. Pass the data back to the main.py file, so that you can print the data from main.py
from data_manager import DataManager
data_manager = DataManager()
sheet_data = data_manager.get_destination_data()
# print(sheet_data)

#  5. In main.py check if sheet_data contains any values for the "iataCode" key.
#  If not, then the IATA Codes column is empty in the Google Sheet.
#  In this case, pass each city name in sheet_data one-by-one
#  to the FlightSearch class to get the corresponding IATA code
#  for that city using the Flight Search API.
#  You should use the code you get back to update the sheet_data dictionary.
if sheet_data[0]["iataCode"] == "":
    from flight_search import FlightSearch
    flight_search = FlightSearch()
    for row in sheet_data:
        row["iataCode"] = flight_search.get_destination_code(row["city"])
    print(sheet_data)
    
    data_manager.destination_data = sheet_data
    data_manager.update_destination_codes()

You can't actually use the flight future schedules API unless you subscribe to the basic plan or a higher plan. I guess that condition and some other limitations, like failure to cover airports with very small traffic—like around 10 or fewer flights per day, and the enforced rate limitation on the endpoint, i.e., each user is allowed to make one API call per minute, and exceeding this limit will result in temporary access restrictions, discouraged Angela from using Aviationstack. So you can either look for an alternative API to use or move on to the next section.