old_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  # This Source Code Form is subject to the terms of the Mozilla Public
  # License, v. 2.0. If a copy of the MPL was not distributed with this
  # file, You can obtain one at http://mozilla.org/MPL/2.0/.
  
  SCHEMA = {
      "type": "object",
      "properties": {
          "body": {"type": "string"},
          "title": {"type": "string"},
          "labels": {
              "type": "array",
              "items": {
                  "type": "string"
              }
  
          },
      },
      "required": ["body", "title"]
  }
  
new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  # This Source Code Form is subject to the terms of the Mozilla Public
  # License, v. 2.0. If a copy of the MPL was not distributed with this
  # file, You can obtain one at http://mozilla.org/MPL/2.0/.
  
  '''Defines a schema to validate against:
  
  body: required, a string
  title: required, a string
  labels: optional, but if included, all strings
  '''
  
  SCHEMA = {
      "type": "object",
      "properties": {
          "body": {"type": "string"},
          "title": {"type": "string"},
          "labels": {
              "type": "array",
              "items": {
                  "type": "string"
              }
  
          },
      },
      "required": ["body", "title"]
  }
  
subject: Add some commments for schema.py