Finds core genes, and records gene names and sequences in dictionaries
        :param record: SeqIO record

def cdsparse(self, record):
        """
        Finds core genes, and records gene names and sequences in dictionaries
        :param record: SeqIO record
        """
        try:
            # Find genes that are present in all strains of interest - the number of times the gene is found is
            # equal to the number of strains. Earlier parsing ensures that the same gene is not present in a strain
            # more than once
            if self.genes[self.genenames[record.id]] == len(self.runmetadata.samples):
                # Add the gene names and sequences to the appropriate dictionaries
                try:
                    self.genesequence[self.genenames[record.id]].add(str(record.seq))
                # Initialise the dictionary as required, then populate as above
                except KeyError:
                    self.genesequence[self.genenames[record.id]] = set()
                    self.genesequence[self.genenames[record.id]].add(str(record.seq))
                try:
                    self.coresequence[str(record.seq)].add(record.id)
                except KeyError:
                    self.coresequence[str(record.seq)] = set()
                    self.coresequence[str(record.seq)].add(record.id)
        except KeyError:
            pass