position_tracker.py 文件源码

def get_positions(self):

        positions = self._positions_store

        for sid, pos in iteritems(self.positions):

            if pos.amount == 0:
                # Clear out the position if it has become empty since the last
                # time get_positions was called.  Catching the KeyError is
                # faster than checking `if sid in positions`, and this can be
                # potentially called in a tight inner loop.
                try:
                    del positions[sid]
                except KeyError:
                    pass
                continue

            # Note that this will create a position if we don't currently have
            # an entry
            position = positions[sid]
            position.amount = pos.amount
            position.cost_basis = pos.cost_basis
            position.last_sale_price = pos.last_sale_price
        return positions