You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: dbgstr.m
    path of file: ./repos/prima/benchmark/rescue_idz/norma/matlab/interfaces/private
    
    the code of the file until where you have to start completion: function s = dbgstr(debug_flag)
%DBGSTR returns a string according to `debug_flag`: 'g' for true (debug) and 'O' for false (not debug).
% This function is used at two places:
% - compile.m, where `dbgstr` is used to generate the MEX options (MEX uses `-g` as the flag for
%   debugging and `-O` for no debugging but optimizing);

    
function s = dbgstr(debug_flag)
%DBGSTR returns a string according to `debug_flag`: 'g' for true (debug) and 'O' for false (not debug).
% This function is used at two places:
% - compile.m, where `dbgstr` is used to generate the MEX options (MEX uses `-g` as the flag for
%   debugging and `-O` for no debugging but optimizing);
% - get_mexname.m, where `dbgstr` is used to generate names of the MEX functions.

if (debug_flag)
    s = 'g';
else
    s = 'O';
end