@staticmethod
def resistance(genename, resistance_dict):
    """
        Determine the resistance class of the gene by searching the sets of genes included in every resistance FASTA
        file
        :param genename: Header string returned from analyses
        :param resistance_dict: Dictionary of resistance class: header
        :return: resistance class of the gene
        """
    resistance_list = list()
    for resistance_class, gene_set in resistance_dict.items():
        if genename in gene_set:
            resistance_list.append(resistance_class)
    resistance = ','.join(sorted(resistance_list))
    return resistance
