关系运算符
```python
class Number:
def __init__(self, num):
self.num = num
# 大于 >
def __gt__(self, other):
print('__gt__')
return self.num > other
# 小于 <
def __lt__(self, other):
print('__lt__')
return self.num < other
# 等于 ==， 判断是否相等，当不实现__ne__时，!=运算也会触发
def __eq__(self, other):
print('__eq__')
return self.num == other
# 大于等于 >=
def __ge__(self, other):
print('__ge__')
return self.num >= other
# 小于等于 <=
def __le__(self, other):
print('__le__')
return self.num <= other
# 不等于 !=
def __ne__(self, other):
print('__ne__')
return self.num != other
n = Number(20)
print(n > 10)
print(n < 10)
print(n == 10)
print(n != 10)
