class product:
    def __init__(self, name: str, price: float, quantity = 0):
        assert price >= 0, "Price must be non-negative"
        assert quantity >= 0, "Quantity must be non-negative"          
        self.name = name
        self.price = price
        self.quantity = quantity

    def calculate_total_price(self) -> float:
        return self.price * self.quantity

    def display_info(self):
        return f"Product: {self.name}, Price: ${self.price:.2f}"



# Example usage:

product1 = product("Laptop", 1999.99, 1) 
print(product1.display_info())  # Output: Item: Laptop, Price: $1999.99
print(product1.calculate_total_price())  # Output: 3999996.0001
product2 = product("Smartphone", 799.99, -3) 
print(product2.display_info())  # Output: Item: Smartphone, Price: $799.99
print(product2.calculate_total_price())  # Output: 2399.97