asset_restrictions.py 文件源码

def __init__(self, restrictions):
        # A dict mapping each asset to its restrictions, which are sorted by
        # ascending order of effective_date
        self._restrictions_by_asset = {
            asset: sorted(
                restrictions_for_asset, key=lambda x: x.effective_date
            )
            for asset, restrictions_for_asset
            in iteritems(groupby(lambda x: x.asset, restrictions))
        }