code: def _prepare_socket_file(self, socket_path, default_prefix):
          
          if socket_path is not None:
              if os.path.exists(socket_path):
                  raise Exception("Socket file {} exists!".format(socket_path))
              socket_dir = os.path.dirname(socket_path)
              try_to_create_directory(socket_dir)
              return socket_path
          return self._make_inc_temp(
              prefix=default_prefix, directory_name=self._sockets_dir)
docs: Prepare the socket file for raylet and plasma.
  
          This method helps to prepare a socket file.
          1. Make the directory if the directory does not exist.
          2. If the socket file exists, raise exception.
  
          Args:
              socket_path (string): the socket file to prepare.