use_cache_true.py

from datetime import datetime

def calculate_users_favorite_color(user, use_cache=True):
  now = datetime.now()
  
  color, valid_until = None, None
  if use_cache:
    color, valid_until = cache.get(f"user_color_{user.id}")

  if not use_cache or (valid_until is not None and valid_until > now):
    
    ...logic...logic...
    color=....
    ...logic...logic...

    if use_cache:
      valid_until = now + datetime.timedelta(days=3, hours=12)
      cache.set(f"user_color_{user.id}", (color, valid_until))

  return color