docs: def do_set(self, line):
          """set [parameter [value]] set (without parameters): Display the value of all
          session variables.
  
          set <session variable>: Display the value of a single session variable. set
          <session variable> <value>: Set the value of a session variable.
  
          """
          session_parameter, value = self._split_args(line, 0, 2)
          if value is None:
              self._command_processor.get_session().print_variable(session_parameter)
          else:
              self._command_processor.get_session().set_with_conversion(
                  session_parameter, value
              )
              self._print_info_if_verbose(
                  'Set session variable {} to "{}"'.format(session_parameter, value)
              )