Add --echo option to cli

pytchat/cli/arguments.py

@@ -19,6 +19,7 @@ class Arguments(metaclass=Singleton):
         OUTPUT: str = 'output_dir'
         VIDEO_IDS: str = 'video_id'
         SAVE_ERROR_DATA: bool = 'save_error_data'
+        ECHO: bool = 'echo'
 
     def __init__(self,
                  arguments: Optional[Dict[str, Union[str, bool, int]]] = None):
@@ -36,8 +37,9 @@ class Arguments(metaclass=Singleton):
         self.output: str = arguments[Arguments.Name.OUTPUT]
         self.video_ids: List[int] = []
         self.save_error_data: bool = arguments[Arguments.Name.SAVE_ERROR_DATA]
-
+        self.echo: bool = arguments[Arguments.Name.ECHO]
         # Videos
+
         if arguments[Arguments.Name.VIDEO_IDS]:
             self.video_ids = [video_id
                               for video_id in arguments[Arguments.Name.VIDEO_IDS].split(',')]