docs: def main():
      """The main function of the module.
  
      These are the steps:
  
      1. Reads the population file (:py:func:`readPopulations`).
      2. Extracts the MDS values (:py:func:`extractData`).
      3. Plots the MDS values (:py:func:`plotMDS`).
  
      """
      # Getting and checking the options
      args = parseArgs()
      checkArgs(args)
  
      # Reads the population file
      populations = readPopulations(args.population_file, args.population_order)
  
      # Acquire the data
      theData, theLabels = extractData(args.file, populations,
                                       args.population_order, args.xaxis,
                                       args.yaxis)
  
      # Plot the data
      plotMDS(theData, args.population_order, theLabels, args.population_colors,
              args.population_alpha, args.population_sizes,
              args.population_markers, args)