code: def get_tables(self) -> DBHandlerResponse:
      if self.client:
          channels = self.client.conversations_list(
              types="public_channel,private_channel"
          )["channels"]
          self.channel_names = [c["name"] for c in channels]
          tables_df = pd.DataFrame(
              self.channel_names, columns=["table_name"]
          )
          return DBHandlerResponse(data=tables_df)
  
file_path: evadb/evadb/third_party/databases/slack/slack_handler.py
imports: import pandas
  from slack_sdk import WebClient
  from slack_sdk.errors import SlackApiError
  from evadb.third_party.types import DBHandler, DBHandlerResponse, DBHandlerStatus
label_desc: Use image node_id 5 for calling the SlackHandler obj's underlying member method code with example usage: obj.get_tables() and returns: DBHandlerResponse