docs: def main():
      """Run the program."""
      args = parse_arguments()
  
      ext = os.path.splitext(args.input_file)[-1].lower()
      with gzip.open(args.output_file, mode='wt') as outfile:
          csvwriter = csv.writer(outfile, delimiter=str('\t'), lineterminator='\n')
  
          try:
              if ext in ('.tab', '.txt', '.tsv'):
                  with open(args.input_file) as infile:
                      for line in infile:
                          outline = line.strip().split('\t')
                          csvwriter.writerow(outline)
              elif ext == '.csv':
                  with open(args.input_file) as infile:
                      for line in infile:
                          outline = line.strip().split(',')
                          csvwriter.writerow(outline)
              elif ext in ('.xls', '.xlsx'):
                  workbook = xlrd.open_workbook(args.input_file)
                  worksheet = workbook.sheets()[0]
                  for rownum in range(worksheet.nrows):
                      csvwriter.writerow(worksheet.row_values(rownum))
              else:
                  print('{"proc.error":"File extension not recognized."}')
          except Exception:
              print('{"proc.error":"Corrupt or unrecognized file."}')
              raise