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: in_events_nwb.m
    path of file: ./repos/brainstorm3/toolbox/io
    
    the code of the file until where you have to start completion: function events = in_events_nwb(sFile, nwb2, nEpochs, ChannelMat)
% IN_EVENTS_NWB Read events from a Neurodata Without Borders file.

% @=============================================================================
% This function is part of the Brainstorm software:
% https://neuroimage.usc.edu/brainstorm
% 
% Copyright (c) University of Southern California & McGill University
% This software is distributed under the terms of the GNU General Public License
% as published by the Free Software Foundation. Further details on the GPLv3
% license can be found at http://www.gnu.org/copyleft/gpl.html.
% 
% FOR RESEARCH PURPOSES ONLY. THE SOFTWARE IS PROVIDED "AS IS," AND THE
% UNIVERSITY OF SOUTHERN CALIFORNIA AND ITS COLLABORATORS DO NOT MAKE ANY
% WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF
% MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, NOR DO THEY ASSUME ANY
% LIABILITY OR RESPONSIBILITY FOR THE USE OF THIS SOFTWARE.
%
% For more information type "brainstorm license" at command prompt.

    
function events = in_events_nwb(sFile, nwb2, nEpochs, ChannelMat)
% IN_EVENTS_NWB Read events from a Neurodata Without Borders file.

% @=============================================================================
% This function is part of the Brainstorm software:
% https://neuroimage.usc.edu/brainstorm
% 
% Copyright (c) University of Southern California & McGill University
% This software is distributed under the terms of the GNU General Public License
% as published by the Free Software Foundation. Further details on the GPLv3
% license can be found at http://www.gnu.org/copyleft/gpl.html.
% 
% FOR RESEARCH PURPOSES ONLY. THE SOFTWARE IS PROVIDED "AS IS," AND THE
% UNIVERSITY OF SOUTHERN CALIFORNIA AND ITS COLLABORATORS DO NOT MAKE ANY
% WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF
% MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, NOR DO THEY ASSUME ANY
% LIABILITY OR RESPONSIBILITY FOR THE USE OF THIS SOFTWARE.
%
% For more information type "brainstorm license" at command prompt.
% =============================================================================@
%
% Authors: Konstantinos Nasiotis, 2019-2021

%% Reads spiking and acquisition events

% Check if an events field exists in the dataset
try
    events_exist = ~isempty(nwb2.stimulus_presentation);
    if ~events_exist
        disp('No events in this .nwb file')
    else
        all_event_keys = keys(nwb2.stimulus_presentation);
        disp(' ')
        disp('The following event types are present in this dataset')
        disp('------------------------------------------------')
        for iEvent = 1:length(all_event_keys)
            disp(all_event_keys{iEvent})
        end