Weather App Implementation

Code a weather app.

Implement a function that returns the latest forecast for a requested city using a weather API response cache. The function should accept a list of requests, where each request is either a lookup for a city or a refresh event that updates that city’s forecast data. Return the forecast value for each lookup in order.

Function signature

def weather_app(requests):

Input

• requests: a list of requests, each request is a dict with fields:
  • type: either "lookup" or "refresh"
  • city: a string
  • forecast: an integer, present only for "refresh"

Output

• Return a list of integers, one per "lookup", representing the current cached forecast for that city, or -1 if the city has not been refreshed yet.

Constraints

• 1 <= len(requests) <= 10^5
• City names contain only lowercase English letters
• Refreshes and lookups may be interleaved in any order