class_docstr: Implementation for the emails table for Gmail
class_docstr_tok: ["Implementation","for","the","emails","table","for","Gmail"]
docstr: Gets all columns to be returned in pandas DataFrame responses
  
  Returns
  -------
  List[str]
      List of columns
docstr_tok: ["Gets","all","columns","to","be","returned","in","pandas","DataFrame","responses","Returns","--","--","--","-","List","[","str","]","List","of","columns"]
code: def get_columns(self) -> List[str]:
      """Gets all columns to be returned in pandas DataFrame responses
  
      Returns
      -------
      List[str]
          List of columns
      """
      return [
          "id",
          "message_id",
          "thread_id",
          "label_ids",
          "sender",
          "to",
          "date",
          "subject",
          "snippet",
          "history_id",
          "size_estimate",
          "body",
          "attachments",
      ]
  
imports: import json
  from shutil import copyfile
  from collections import OrderedDict
  import requests
  from mindsdb.integrations.libs.response import HandlerStatusResponse, HandlerResponse
  from mindsdb.integrations.libs.const import HANDLER_CONNECTION_ARG_TYPE
  from mindsdb.integrations.utilities.sql_utils import extract_comparison_conditions
  from mindsdb.integrations.libs.api_handler import APIHandler, APITable
  from mindsdb_sql.parser import ast
  from mindsdb.utilities import log
  from mindsdb_sql import parse_sql
  from mindsdb.utilities.config import Config
  import os
  import time
  from typing import List
  import pandas
  from google.auth.transport.requests import Request
  from google.oauth2.credentials import Credentials
  from google_auth_oauthlib.flow import Flow
  from googleapiclient.discovery import build
  from googleapiclient.errors import HttpError
  from email.message import EmailMessage
  from base64 import urlsafe_b64encode, urlsafe_b64decode
  from .utils import AuthException, google_auth_flow, save_creds_to_file
label_desc: Use image node_id 2 for calling the EmailsTable obj's underlying member method code with example usage: obj.get_columns() and returns: list