def sa_obj_to_dict(obj, filtrate=None, rename=None):     """     sqlalchemy 对象转为dict     :param filtrate: 过滤的字段     :type filtrate: list or tuple     :param rename: 需要改名的,改名在过滤之后处理, key为原来对象的属性名称，value为需要更改名称     :type rename: dict     :rtype: dict     """     if isinstance(obj.__class__, DeclarativeMeta):         # an SQLAlchemy class         #该类的相关类型，即直接与间接父类         cla = obj.__class__.__mro__         #过滤不需要的父类         cla = filter(lambda c: hasattr(c, '__table__'), filter(lambda c: isinstance(c, DeclarativeMeta), cla))         columns = []         map(lambda c: columns.extend(c.__table__.columns), cla[::-1])         # columns = obj.__table__.columns         if filtrate and isinstance(filtrate, (list, tuple)):             fields = dict(map(lambda c: (c.name, getattr(obj, c.name)), filter(lambda c: not c.name in filtrate, columns)))         else:             fields = dict(map(lambda c: (c.name, getattr(obj, c.name)), columns))         # fields = dict([(c.name, getattr(obj, c.name)) for c in obj.__table__.columns])         if rename and isinstance(rename, dict):             #先移除key和value相同的项             _rename = dict(filter(lambda (k, v): str(k) != str(v), rename.iteritems()))             #如果原始key不存在，那么新的key对应的值默认为None             #如果新的key已存在于原始key中，那么原始key的值将被新的key的值覆盖             # map(lambda (k, v): fields.setdefault(v, fields.pop(k, None)), _rename.iteritems())             map(lambda (k, v): fields.update({v: fields.pop(k, None)}), _rename.iteritems())         #         return fields     else:         return {}