new_contents: from flask import Flask
  from parsl.monitoring.visualization.models import db
  import argparse
  
  
  def cli_run():
      """ Instantiates the Monitoring viz server
      """
      parser = argparse.ArgumentParser(description='Parsl visualization tool')
      parser.add_argument('db_path', type=str,
                          help='Database path in the format sqlite:///<absolute_path_to_db>')
      parser.add_argument('--port', type=int, default=8080,
                          help='Port at which the monitoring Viz Server is hosted. Default: 8080')
      parser.add_argument("-d", "--debug", action='store_true',
                          help="Enable debug logging")
      parser.add_argument("-e", "--external", action='store_true',
                          help="Enable hosting on Internet")
      args = parser.parse_args()
  
      app = Flask(__name__)
      app.config['SQLALCHEMY_DATABASE_URI'] = args.db_path
      app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
      db.init_app(app)
  
      with app.app_context():
          db.create_all()
          from parsl.monitoring.visualization import views
          views.dummy = False
          host = '127.0.0.1'
          if args.external:
              host = '0.0.0.0'
          app.run(host=host, port=args.port, debug=args.debug)
  
  
  if __name__ == "__main__":
      cli_run()
  
subject: Add missing app.py