code: def check(self):
      assert self.host is not None
      assert self.port is not None
      assert self.user is not None
      assert self.password is not None
      assert self.instance is not None
      assert self.connection_name is not None
      if self.ssl_cert is not None:
          assert self.ssl_key is not None
          if not os.path.isfile(self.ssl_cert):
              raise ValueError(
                  f"specified ssl-cert, {self.ssl_cert}, does not exist"
              )
          if not os.path.isfile(self.ssl_key):
              raise ValueError(
                  f"specified ssl-key, {self.ssl_key}, does not exist"
              )
      else:
          assert self.ssl_key is None
      assert self.ssl_ca is not None
      if not os.path.isfile(self.ssl_ca):
          raise ValueError(
              f"specified ssl-ca, {self.ssl_ca}, does not exist"
          )
  
file_path: hail/hail/python/hailtop/auth/sql_config.py
imports: from typing import Dict, NamedTuple, Optional, Any
  import json
  import os
label_desc: Use image node_id 4 for calling the SQLConfig obj's underlying member method code with example usage: obj.check() without return types