code: def extract_data(self, indexer: "HistogramIndexer"):
      data = {}
      for name, value_container in self._data.items():
          node_data_list = value_container.extract_node_data(
              indexer.node_axis_stride, indexer.node_size
          )
          for nid, node_data in enumerate(node_data_list):
              if nid not in data:
                  data[nid] = {}
              data[nid][name] = node_data
      return data
  
imports: import typing
  from typing import MutableMapping
  from ._value import HistogramValues
  from ._plain import HistogramPlainValues
  from ._cipher import HistogramEncryptedValues
label_desc: Use image node_id 16 for calling the HistogramValuesContainer obj's underlying member method code with example usage: obj.extract_data(indexer) and returns: data