input: from typing import List
  
  def list_all_countries_api() -> str:
      """Create a basic REST API using Python and Flask to list all the countries in the world.
      The API should serve data from a JSON file.
      Example:
      >>> list_all_countries_api()
      "import flask\\nfrom flask import Flask, request, jsonify\\nimport json\\n\\napp = Flask(name)\\n\\n@app.route('/countries', methods=['GET'])\\ndef get_countries():\\n with open('data.json', 'r') as f:\\n countries = json.load(f)\\n return jsonify(countries)\\n\\nif name == 'main':\\n app.run()\\n"
      """
output:     return """import flask
  from flask import Flask, request, jsonify
  import json
  
  app = Flask(__name__)
  
  @app.route('/countries', methods=['GET'])
  def get_countries():
      with open('data.json', 'r') as f:
          countries = json.load(f)
      return jsonify(countries)
  
  if __name__ == '__main__':
      app.run()
  """