This function takes epitope length as input into epi_length object. Input data for this function is present in "/data_mycobacrvR/netmhcNN_out" directory, therefore 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".