docs: def remove_stage_from_deployed_values(key, filename):
      # type: (str, str) -> None
      """Delete a top level key from the deployed JSON file."""
      final_values = {}  # type: Dict[str, Any]
      try:
          with open(filename, 'r') as f:
              final_values = json.load(f)
      except IOError:
          # If there is no file to delete from, then this funciton is a noop.
          return
  
      try:
          del final_values[key]
          with open(filename, 'wb') as f:
              data = serialize_to_json(final_values)
              f.write(data.encode('utf-8'))
      except KeyError:
          # If they key didn't exist then there is nothing to remove.
          pass