class_docstr: Stores all actual data and typing information for an entityset
  
  Attributes:
      id
      dataframe_dict
      relationships
      time_type
  
  Properties:
      metadata
class_docstr_tok: ["Stores","all","actual","data","and","typing","information","for","an","entityset","Attributes",":","id","dataframe_dict","relationships","time_type","Properties",":","metadata"]
docstr: Sets the secondary time index for a Woodwork dataframe passed in
docstr_tok: ["Sets","the","secondary","time","index","for","a","Woodwork","dataframe","passed","in"]
code: def _set_secondary_time_index(self, dataframe, secondary_time_index):
      """Sets the secondary time index for a Woodwork dataframe passed in"""
      assert (
          dataframe.ww.schema is not None
      ), "Cannot set secondary time index if Woodwork is not initialized"
      self._check_secondary_time_index(dataframe, secondary_time_index)
      if secondary_time_index is not None:
          dataframe.ww.metadata[
              "secondary_time_index"
          ] = secondary_time_index
  
imports: import copy
  import logging
  import warnings
  from collections import defaultdict
  import numpy
  import pandas
  from woodwork import init_series
  from woodwork.logical_types import Datetime, LatLong
  from featuretools.entityset import deserialize, serialize
  from featuretools.entityset.relationship import Relationship, RelationshipPath
  from featuretools.feature_base.feature_base import _ES_REF
  from featuretools.utils.gen_utils import Library, import_or_none, is_instance
  from featuretools.utils.plot_utils import check_graphviz, get_graphviz_format, save_graph
  from featuretools.utils.wrangle import _check_timedelta
label_desc: Use image node_id 20 for calling the EntitySet obj's underlying member method code with example usage: obj._set_secondary_time_index(dataframe, secondary_time_index) without return types