[backtrader source code analysis 51] simple interpretation of the source code of seven files in observers (boring, for reference only)

observers Some classes in are mainly used to display some transactions when drawing , Account amount, etc . I personally think the starting point is very good , The functions implemented are also good , Very scalable , But and analyzer equally , A lot of things don't have to exist , Write a function directly at the bottom , Save daily value,cash,order,trade,position , etc. , Then analyze the data , Will it be more efficient ？

trades.py

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

import uuid

from .. import Observer
from .