【backtrader源码解析35】observer.py源码注释(枯燥，仅供参考)

observer.py的源代码注释,总体上代码比较简单

from __future__ import (absolute_import, division, print_function,
                        unicode_literals)


from .lineiterator import LineIterator, ObserverBase, StrategyBase
from backtrader.utils.py3 import with_metaclass

# Observer元类
class