code: def to_dict(self, into=dict):
          
          # GH16122
          into_c = com.standardize_mapping(into)
          return into_c(self.items())
docs: Convert Series to {label -> value} dict or dict-like object.
  
          Parameters
          ----------
          into : class, default dict
              The collections.abc.Mapping subclass to use as the return
              object. Can be the actual class or an empty
              instance of the mapping type you want.  If you want a
              collections.defaultdict, you must pass it initialized.
  
              .. versionadded:: 0.21.0
  
          Returns
          -------
          collections.abc.Mapping
              Key-value representation of Series.
  
          Examples
          --------
          >>> s = pd.Series([1, 2, 3, 4])
          >>> s.to_dict()
          {0: 1, 1: 2, 2: 3, 3: 4}
          >>> from collections import OrderedDict, defaultdict
          >>> s.to_dict(OrderedDict)
          OrderedDict([(0, 1), (1, 2), (2, 3), (3, 4)])
          >>> dd = defaultdict(list)
          >>> s.to_dict(dd)
          defaultdict(<class 'list'>, {0: 1, 1: 2, 2: 3, 3: 4})