switch 语句编写一个简单的四则运算

def calculate(operator: str, num1: float, num2: float) -> float:
    """
    A simple function to perform arithmetic operations on num1 and num2 based on the operator provided.
    """
    result = 0
    # Use switch case to implement arithmetic operations
    switcher = {
        '+': num1 + num2,
        '-': num1 - num2,
        '*': num1 * num2,
        '/': num1 / num2
    }
    result = switcher.get(operator, "Invalid operator")
    return result
    
# Example usage
print(calculate('+', 5, 3)) # Output: 8
print(calculate('-', 5, 3)) # Output: 2
print(calculate('*', 5, 3)) # Output: 15
print(calculate('/', 5, 3)) # Output: 1.6666666666666667
print(calculate('^', 5, 3)) # Output: Invalid operator