| 1 | class Chain(): |
| 2 | def __init__(self, val): |
| 3 | self.val = val |
| 4 | |
| 5 | def add(self, b): |
| 6 | self.val += b |
| 7 | return self |
| 8 | |
| 9 | def sub(self, b): |
| 10 | self.val -= b |
| 11 | return self |
| 12 | |
| 13 | def mul(self, b): |
| 14 | self.val *= b |
| 15 | return self |
| 16 | |
| 17 | |
| 18 | print(Chain(5).add(5).sub(2).mul(10)) |