73     def diff_diff(self, other):  argument
84     def ratio(self, other):  argument
100     def __add__(self, other):  argument
103     def __sub__(self, other):  argument
106     def __mul__(self, other):  argument
140     def diff_diff(self, other):  argument
147     def ratio(self, other):  argument
154     def __add__(self, other):  argument
157     def __sub__(self, other):  argument
160     def __mul__(self, other):  argument
163     def __lt__(self, other):  argument
168     def __gt__(self, other):  argument
171     def __le__(self, other):  argument
174     def __ge__(self, other):  argument
194     def __add__(self, other):  argument