docs: def fasta_stats(files, records):
      """
      Parse the lengths of all contigs for each sample, as well as the total GC%
      :param files: dictionary of stain name: /sequencepath/strain_name.extension
      :param records: Dictionary of strain name: SeqIO records
      :return: contig_len_dict, gc_dict: dictionaries of list of all contig length, and total GC% for all strains
      """
      # Initialise dictionaries
      contig_len_dict = dict()
      gc_dict = dict()
      for file_name in files:
          # Initialise variables to store appropriate values parsed from contig records
          contig_lengths = list()
          fasta_sequence = str()
          for contig, record in records[file_name].items():
              # Append the length of the contig to the list
              contig_lengths.append(len(record.seq))
              # Add the contig sequence to the string
              fasta_sequence += record.seq
          # Set the reverse sorted (e.g. largest to smallest) list of contig sizes as the value
          contig_len_dict[file_name] = sorted(contig_lengths, reverse=True)
          # Calculate the GC% of the total genome sequence using GC - format to have two decimal places
          gc_dict[file_name] = float('{:0.2f}'.format(GC(fasta_sequence)))
      return contig_len_dict, gc_dict