code: def _check_data(self, X):
          '''
          Checks that unique identifiers vaf_types are consistent between time series.
  
          Parameters
          ----------
          X : array-like, shape [n_series, ...]
              Time series data and (optionally) contextual data
          '''
  
          if len(X) > 1:
              sval = np.unique(X[0][:, 1])
              if np.all([np.all(np.unique(X[i][:, 1]) == sval) for i in range(1, len(X))]):
                  pass
              else:
                  raise ValueError("Unique identifier var_types not consistent between time series"f _check_data(self, X):
          '''
          Checks that unique identifiers vaf_types are consistent between time series.
  
          Parameters
          ----------
          X : array-like, shape [n_series, ...]
              Time series data and (optionally) contextual data
          '''
  
          if len(X) > 1:
              sval = np.unique(X[0][:, 1])
              if np.all([np.all(np.unique(X[i][:, 1]) == sval) for i in range(1, len(X))]):
                  pass
              else:
                  raise ValueError("Unique identifier var_types not consistent between time series")
docs: Checks that unique identifiers vaf_types are consistent between time series.
  
          Parameters
          ----------
          X : array-like, shape [n_series, ...]
              Time series data and (optionally) contextual data