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: pop_micro_smooth.m
    path of file: ./repos/Microstate-EEGlab-toolbox/Microstate1.0
    
    the code of the file until where you have to start completion: % pop_micro_smooth() - Temporally smooths microstate labels
%  
% Temporally smooths microstate labels obtained either from segmentation or
% from backfitting. The labels should be stored in either 
% EEG.microstate.labels or EEG.microstate.fit.labels, correspondingly.
%
% Usage:
%   >> EEG = pop_micro_smooth ( EEG ); % pop up window
%   >> EEG = pop_micro_smooth ( EEG, 'key1', 'val1')
%
% Please cite this toolbox as:
% Poulsen, A. T., Pedroni, A., Langer, N., &  Hansen, L. K. (unpublished
% manuscript). Microstate EEGlab toolbox: An introductionary guide.
%
% Inputs:
%   EEG  - EEGlab EEG structure with microstate field.
%
% Optional input:
%  'label_type'  - Smoo
    
function
smooth_str = dropdown_smooth{1}; %string for popupmenu
for s = 2:length(dropdown_smooth); smooth_str = [smooth_str '|' dropdown_smooth{s}]; end
line.smooth_type = { {'Style' 'text' 'string' 'Choose smoothing method:'}, ...
    {'Style' style.smooth_type 'string' smooth_str 'tag' 'smooth_type' 'value' 1} };
geo.smooth_type = {[1 1]};


%% Order inputs for GUI
geometry = [geo.label_type geo.smooth_type];
uilist = [line.label_type line.smooth_type];


%% Create Popup
[~,~,~,pop_out] = inputgui( geometry, uilist, ...
    'pophelp(''pop_micro_smooth'');', 'Smooths microstate labels -- pop_micro_smooth()');
 

%% Interpret output from popup
if isstruct(pop_out)
    settings = struct;
    settings = interpret_popup(pop_out, settings, style, popmenu);
else
    settings = 'cancel';
end