code: def _get_array_serializer(self):
          
          if not self._items:
              raise ValueError('Must specify \'items\' for \'array\' type')
  
          field = SchemaField(self._items)
  
          def encode(value, field=field):
              if not isinstance(value, list):
                  value = [value]
  
              return [field.encode(i) for i in value]
  
          def decode(value, field=field):
              return [field.decode(i) for i in value]
  
          return (encode, decode)
docs: Gets the encoder and decoder for an array. Uses the 'items' key to
          build the encoders and decoders for the specified type.