find_max_object.py

In [1]: class One:
   ...:     def __init__(self):
   ...:         self.bw_rate = 1
   ...:

In [2]: class Two:
   ...:     def __init__(self):
   ...:         self.bw_rate = 0
   ...:

In [3]: from operator import attrgetter

In [4]: max(One(), Two(), key=attrgetter('bw_rate'))
Out[4]: <__main__.One at 0x103f01978>

In [5]: max(One(), Two(), key=attrgetter('bw_rate')).__dict__
Out[5]: {'bw_rate': 1}