def get_order_quantities(table_orders: dict[str, list[str]]) -> dict[str, int]:
    """Return a mapping from food item to the number of that item ordered.

    In the input dictionary table_orders:
        - Each key is the name of a person.
        - Each corresponding value is a list of the food items that person has ordered.
          Duplicates are allowed!

    In the returned dictionary:
        - Each key a a food item.
        - Each corresponding value is the number of times that food item was ordered
          in table_orders, across all people.

    Use a for loop with a dictionary accumulator, and use mutating operations to update
    the accumulator in the loop body.

    >>> orders = {'David': ['Vegetarian stew', 'Poutine', 'Vegetarian stew'],\
                  'Mario': ['Steak pie', 'Poutine', 'Vegetarian stew'],\
                  'Jen': ['Steak pie', 'Steak pie']}
    >>> get_order_quantities(orders) == {'Vegetarian stew': 3, 'Poutine': 2, 'Steak pie': 3}
    True
    """
    # Accumulator
    quantities = {}
    for key in table_orders:
        for item in table_orders[key]:
            if item not in quantities:
                quantities[item] = 0
            quantities[item] += 1
    return quantities