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: convert_sequences.m
    path of file: ./repos/toolkit-legacy/sequence
    
    the code of the file until where you have to start completion: function converted_sequences = convert_sequences(sequences, converter)
% convert_sequences Converts sequences using a converter
%
% This functions is an utility function that converts a set of sequences using 
% a given converter. The benefit of using this function is that each sequence
% is checked if it was already converted.

    
function converted_sequences = convert_sequences(sequences, converter)
% convert_sequences Converts sequences using a converter
%
% This functions is an utility function that converts a set of sequences using 
% a given converter. The benefit of using this function is that each sequence
% is checked if it was already converted.
%
% Input:
% - sequences (cell): Cell array of sequence structures.
% - converter (function, string): A function handle or a string that can be resolved to a converter function.
%
% Output:
% - converted_sequences (cell): Cell array of converted sequence structures.

if isempty(converter)
    converted_sequences = sequences;
    return;
end