class_docstr: Special class of TsData, which can be partitioned.
  Derived classes should implement __iter__ and __len__.
code: def __init__(self, df, column_id):
      self.df_id_type = df[column_id].dtype
  
imports: import itertools
  from collections import defaultdict, namedtuple
  from typing import Iterable, Sized
  import pandas
label_desc: Use image node_id 1 to create a new PartitionedTsData object from inherited base classes: Iterable, Sized, TsData with example: obj = PartitionedTsData(df, column_id)