
    Write a function that analyzes a list of delivery route options, where each option consists of a route ID and its estimated completion time in minutes, and returns the route ID that has the shortest estimated delivery time. The function should help dispatchers quickly identify the most time-efficient route from all available options.
    

    
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that analyzes a list of delivery route options, where each option consists of a route ID and its estimated completion time in minutes, and returns the route ID that has the shortest estimated delivery time. The function should help dispatchers quickly identify the most time-efficient route from all available options.
    

    """
from operator import itemgetter

def index_minimum(test_list):
    """
    Write a function that analyzes a list of delivery route options, where each option consists of a route ID and its estimated completion time in minutes, and returns the route ID that has the shortest estimated delivery time. The function should help dispatchers quickly identify the most time-efficient route from all available options.
    

    """
    res = min(test_list, key=itemgetter(1))[0]
    return res