docs: def main(argString=None):
      """The main function of the module.
  
      :param argString: the options.
  
      :type argString: list
  
      These are the steps:
  
      1. Prints the options.
      2. Checks the number of samples in the ``tfam`` file
         (:py:func:`compute_nb_samples`).
      3. Computes the heterozygosity rate (:py:func:`compute_heterozygosity`).
      4. Saves the heterozygosity data (in ``out.het``).
      5. Plots the heterozygosity rate (:py:func:`plot_heterozygosity`).
  
      """
      # Getting and checking the options
      args = parseArgs(argString)
      checkArgs(args)
  
      # Check the number of samples
      nb_samples = compute_nb_samples(args.tfile)
  
      # Compute the heterozygosity rate
      heterozygosity, samples = compute_heterozygosity(args.tfile, nb_samples)
  
      # Save heterozygosity data
      save_heterozygosity(heterozygosity, samples, args.out)
  
      # Plotting the heterozygosity rate distribution
      plot_heterozygosity(heterozygosity, args)