This function takes epitope length as input into epi_length object. Input data for this function is present in "/data_mycobacrvR/netmhcWT_out" directory, therefore set this directory as working directory before using this function. NetMHC server 3.0 provides epitopes by selecting window size of epitope length such as 8mer, 9mer, 10mer, 11mer. Therefore epi_length should be given as "10mer".