old_contents: #!/usr/bin/env python
  
  if __name__ == "__main__":
      run()
  
new_contents: #!/usr/bin/env python
  
  """Simple Genetic Algorithm for solving TSP.
  
  Usage:
    main.py FILE --pop-size=POP_SIZE --max-gen=MAX_GENERATIONS --xover-rate=CROSSOVER_RATE --mute-rate=MUTATION_RATE --num-elites=NUM_ELITES --tournament-k=K
    main.py (-h | --help)
    main.py (-v | --version)
  
  Options:
    -h --help     Show this screen.
    -v --version  Show version.
  
  """
  from docopt import docopt
  
  class Genotype(object):
      """The population of chromosomes."""
  
      def __init__(self, population, elite):
          self.population = population
          # TODO: new_pop?
          self.elite = elite
  
  if __name__ == '__main__':
      arguments = docopt(__doc__, version='0.1')
      print(arguments)
      # TODO
      # read file
      # initialize pop
      # run ga (break down)
  
  # Default crossover is PMX. Can also use CX.
  
subject: Build interface w/ docopt and add POD