input: from typing import List, Dict
  
  def calculate_total_cart_cost(items: List[Dict[str, float]], shipping_cost: float, tax_rate: float) -> float:
      """ Calculate the total cost of a shopping cart taking into account
      the item prices, quantity, shipping cost, and tax rate.
      >>> items = [{"name": "widget", "price": 10, "quantity": 5}, {"name": "thingy", "price": 7, "quantity": 3}, {"name": "doodad", "price": 5, "quantity": 2}]
      >>> shipping_cost = 7.50
      >>> tax_rate = 0.095
      >>> calculate_total_cart_cost(items, shipping_cost, tax_rate)
      105.1125
      """
output:     total_item_cost = sum(item["price"] * item["quantity"] for item in items)
      total_cost_before_tax = total_item_cost + shipping_cost
      total_cost = total_cost_before_tax * (1 + tax_rate)
      return round(total_cost, 4)