自定义Python sgn函数处理异常值

def sgn(x):
    try:
        if x > 0:
            return 1
        elif x < 0:
            return -1
        else:
            return 0
    except TypeError:
        print("Error: Input must be a numeric value")
    except Exception as e:
        print("An error occurred:", e)

# Test the sgn function with some values
print(sgn(5))  # Output: 1
print(sgn(-3))  # Output: -1
print(sgn(0))  # Output: 0
print(sgn('a'))  # Output: Error: Input must be a numeric value