Parse the outputs from bbmerge to extract the total number of reads, as well as the number of reads that
        could be paired
        :param err_log: bbmerge outputs the stats in the error file
        :return: num_reads, the total number of reads, paired_reads, number of paired readds

def reads(err_log):
        """
        Parse the outputs from bbmerge to extract the total number of reads, as well as the number of reads that
        could be paired
        :param err_log: bbmerge outputs the stats in the error file
        :return: num_reads, the total number of reads, paired_reads, number of paired readds
        """
        # Initialise variables
        num_reads = 0
        paired_reads = 0
        # Open the log file
        with open(err_log, 'r') as error_log:
            # Extract the necessary information
            for line in error_log:
                if 'Pairs:' in line:
                    num_reads = line.split('\t')[-1].rstrip()
                elif 'Joined:' in line:
                    paired_reads = line.split('\t')[-2].rstrip()
        return num_reads, paired_reads