code: def _ensure_connected(self):
      if self.ctx is not None:
          return
      import snowflake.connector
  
      logging.getLogger("snowflake").setLevel(logging.WARNING)
      # Snowflake prints a scary "Don't know how to construct
      # ResultBatches from response..." error when doing a select
      # with no results.
      logging.getLogger("snowflake.connector.result_batch").setLevel(
          logging.CRITICAL
      )
  
      try:
          self.ctx = snowflake.connector.connect(
              user=self.user,
              account=self.account,
              database=self.database,
              schema="public",
              password=self.password,
              authenticator="externalbrowser"
              if self.use_browser_auth
              else "snowflake",
              autocommit=self.autocommit,
              client_prefetch_thread=16,
              client_session_keep_alive=True,
              warehouse=self.warehouse,
              paramstyle=self.paramstyle,
          )
      except snowflake.connector.errors.DatabaseError as e:
          raise SnowflakeError(
              f"""Failed to connect to database: {e}
  (HINT: if running on a server, you may want to set SNOWFLAKE_PASSWORD=... to use password authentication)"""
          )
  
file_path: evals/evals/utils/snowflake.py
imports: import logging
  import os
  import time
  from contextlib import contextmanager
  from typing import Optional
label_desc: Use image node_id 2 for calling the SnowflakeConnection obj's underlying member method code with example usage: obj._ensure_connected() without return types