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: read_biosig_data.m
    path of file: ./repos/spm12/external/fieldtrip/fileio/private
    
    the code of the file until where you have to start completion: function [dat] = read_biosig_data(filename, hdr, begsample, endsample, chanindx)

% READ_BIOSIG_DATA reads data from EEG file using the BIOSIG

    
function [dat] = read_biosig_data(filename, hdr, begsample, endsample, chanindx)

% READ_BIOSIG_DATA reads data from EEG file using the BIOSIG
% toolbox and returns it in the FCDC framework standard format
%
% Use as
%  [dat] = read_biosig_data(filename, hdr, begsample, end