想在portfoliostrategy中获取策略当前所有持仓合约，在template中写了一个函数，添加策略时总是报如下错误，不知道是哪里的问题，求教。

Traceback (most recent call last):
File "D:\Software\vnpy\lib\site-packages\vnpy_portfoliostrategy\ui\widget.py", line 143, in add_strategy
self.strategy_engine.add_strategy(
File "D:\Software\vnpy\lib\site-packages\vnpy_portfoliostrategy\engine.py", line 380, in add_strategy
self.save_strategy_setting()
File "D:\Software\vnpy\lib\site-packages\vnpy_portfoliostrategy\engine.py", line 626, in save_strategy_setting
save_json(self.setting_filename, strategy_setting)
File "D:\Software\vnpy\lib\site-packages\vnpy\trader\utility.py", line 118, in save_json
json.dump(
File "D:\Software\vnpy\lib\json__init.py", line 179, in dump
for chunk in iterable:
File "D:\Software\vnpy\lib\json\encoder.py", line 431, in _iterencode
yield from _iterencode_dict(o, _current_indent_level)
File "D:\Software\vnpy\lib\json\encoder.py", line 405, in _iterencode_dict
yield from chunks
File "D:\Software\vnpy\lib\json\encoder.py", line 405, in _iterencode_dict
yield from chunks
File "D:\Software\vnpy\lib\json\encoder.py", line 438, in _iterencode
o = _default(o)
File "D:\Software\vnpy\lib\json\encoder.py", line 179, in default
raise TypeError(f'Object of type {o.class.name__} '
TypeError: Object of type ndarray is not JSON serializable

策略参数中，包含了无法序列化的数据类型，截图下你策略代码里的parameteres和variables部分？

MTF wrote:

策略参数中，包含了无法序列化的数据类型，截图下你策略代码里的parameteres和variables部分？
我只是在portfoliostrategy的template中加了一个函数，就是一楼图里的get_all_pos(),没有变动其他部分。self.pos存放的是标的及数量，我只是用了self.pos的keys.

你添加的内容看着没啥问题，而且报错也不是说这里函数代码的解析有问题了

报错就是在engine的save_strategy_setting的时候有问题，可以自己打印一下。不是策略的vt_symbols变成了ndarray，就是策略的parameters里面有值是ndarray