Files
practical-python/Solutions/9_5/porty-app/porty/portfolio.py
David Beazley a31a9ee0f4 object patch
2020-05-28 17:52:19 -05:00

52 lines
1.2 KiB
Python

# portfolio.py
from . import fileparse
from . import stock
class Portfolio:
def __init__(self):
self._holdings = []
@classmethod
def from_csv(cls, lines, **opts):
self = cls()
portdicts = fileparse.parse_csv(lines,
select=['name','shares','price'],
types=[str,int,float],
**opts)
for d in portdicts:
self.append(stock.Stock(**d))
return self
def append(self, holding):
self._holdings.append(holding)
def __iter__(self):
return self._holdings.__iter__()
def __len__(self):
return len(self._holdings)
def __getitem__(self, index):
return self._holdings[index]
def __contains__(self, name):
return any(s.name == name for s in self._holdings)
@property
def total_cost(self):
return sum(s.shares * s.price for s in self._holdings)
def tabulate_shares(self):
from collections import Counter
total_shares = Counter()
for s in self._holdings:
total_shares[s.name] += s.shares
return total_shares