code: def dumps(obj):
      
      (data, schema) = to_serializable(obj)
      return _json.dumps({'data': data, 'schema': schema})
docs: Dumps a serializable object to JSON. This API maps to the Python built-in
      json dumps method, with a few differences:
  
      * The return value is always valid JSON according to RFC 7159.
      * The input can be any of the following types:
          - SFrame
          - SArray
          - SGraph
          - single flexible_type (Image, int, long, float, datetime.datetime)
          - recursive flexible_type (list, dict, array.array)
          - recursive variant_type (list or dict of all of the above)
      * Serialized result includes both data and schema. Deserialization requires
        valid schema information to disambiguate various other wrapped types
        (like Image) from dict.