引入了最新版本的json_model和json_serializable,进行get dependencies出错:

Because json_model 0.0.2 depends on json_serializable ^2.0.0 and no versions of json_model match >0.0.2 <0.1.0, json_model ^0.0.2 requires json_serializable ^2.0.0.
So, because web_socket depends on both json_serializable ^3.2.2 and json_model ^0.0.2, version solving failed.
引入了最新版本的json_model和json_serializable,进行get dependencies出错:

Because json_model 0.0.2 depends on json_serializable ^2.0.0 and no versions of json_model match >0.0.2 <0.1.0, json_model ^0.0.2 requires json_serializable ^2.0.0.
So, because web_socket depends on both json_serializable ^3.2.2 and json_model ^0.0.2, version solving failed.