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: spm_cfg_eeg_copy.m
    path of file: ./repos/spm/config
    
    the code of the file until where you have to start completion: function copy = spm_cfg_eeg_copy
% Configuration file for copying M/EEG datasets
%__________________________________________________________________________

% Vladimir Litvak
% Copyright (C) 2009-2022 Wellcome Centre for Human Neuroimaging


%--------------------------------------------------------------------------
% copy
%--------------------------------------------------------------------------
copy          = cfg_exbranch;
copy.tag      = 'copy';
copy.name     = 'Copy';
copy.val      = @copy_cfg;
copy.help     = {'Copying M/EEG datasets'}';
copy.prog     = @eeg_copy;
copy.vout     = @vout_eeg_copy;
copy.modality = {'EEG'};


%==========================================================================
function varargout = copy_cfg

persistent cfg
if ~isempty(cfg), varargout = {cfg}; return; end

%--------------------------------------------------------------------------
% D
%--------------------------------------------------------------------------
D        = cfg_files;
D.tag    = 'D';
D.name   = 'File Name';
D.filter = 'mat';
D.num    = [1 1];
D.help   = {'Select the M/EEG mat file.'};

%--------------------------------------------------------------------------
% outfile
%--------------------------------------------------------------------------

    
function copy = spm_cfg_eeg_copy
% Configuration file for copying M/EEG datasets
%__________________________________________________________________________

% Vladimir Litvak
% Copyright (C) 2009-2022 Wellcome Centre for Human Neuroimaging


%--------------------------------------------------------------------------
% copy
%--------------------------------------------------------------------------
copy          = cfg_exbranch;
copy.tag      = 'copy';
copy.name     = 'Copy';
copy.val      = @copy_cfg;
copy.help     = {'Copying M/EEG datasets'}';
copy.prog     = @eeg_copy;
copy.vout     = @vout_eeg_copy;
copy.modality = {'EEG'};


%==========================================================================
function varargout = copy_cfg

persistent cfg
if ~isempty(cfg), varargout = {cfg}; return; end

%--------------------------------------------------------------------------
% D
%--------------------------------------------------------------------------
D        = cfg_files;
D.tag    = 'D';
D.name   = 'File Name';
D.filter = 'mat';
D.num    = [1 1];
D.help   = {'Select the M/EEG mat file.'};

%--------------------------------------------------------------------------
% outfile
%--------------------------------------------------------------------------
outfile         = cfg_entry;
outfile.tag     = 'outfile';
outfile.name    = 'Output filename';
outfile.strtype = 's';
outfile.num     = [0 inf];
outfile.help    = {'Choose filename.'};

[cfg,varargout{1}] = deal({D, outfile});


%==========================================================================
function out = eeg_copy(job)
% construct the S struct
S           = job;
S.D         = S.D{1};
out.D       = spm_eeg_copy(S);
out.Dfname  = {fullfile(out.D)};

%==========================================================================
function dep = vout_eeg_copy(job)
% return depend