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: fetch_mics_data.m
    path of file: ./repos/BrainStat/brainstat_matlab/datasets
    
    the code of the file until where you have to start completion: function [thickness, demographics] = fetch_mics_data(options)
% FETCH_MICS_DATA    fetches thickness and demographic MICS data
%   [thickness, demographics] = FETCH_MICS_DATA(data_dir) fetches MICS
%   cortical thickness and demographics data. The following name-value
%   pairs are allowed:

    
function [thickness, demographics] = fetch_mics_data(options)
% FETCH_MICS_DATA    fetches thickness and demographic MICS data
%   [thickness, demographics] = FETCH_MICS_DATA(data_dir) fetches MICS
%   cortical thickness and demographics data. The following name-value
%   pairs are allowed:
%
%   'data_dir'
%       The directory to save the data. Defaults to
%       $HOME/brainstat_data/mics_data
%   'overwrite'
%       If true, overwrites older files. Defaults to false.

arguments
    options.data_dir (1,1) string = brainstat_utils.get_brainstat_directories('mics_data_dir')
    options.overwrite (1,1) logical = false
end