old_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  from {{cookiecutter.repo_name}} import {{cookiecutter.app_class_name}}
  
  def main():
      {{cookiecutter.app_class_name}}().run()
  
  
  if __name__ == '__main__'
      main()
new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  from {{cookiecutter.repo_name}} import {{cookiecutter.app_class_name}}
  
  def main():
      {{cookiecutter.app_class_name}}().run()
  
  
  if __name__ == '__main__':
      main()
subject: Update to main.py