class_docstr: Data handling class which knows how to reattach pandas metadata to model
  results
class_docstr_tok: ["Data","handling","class","which","knows","how","to","reattach","pandas","metadata","to","model","results"]
code: def _check_integrity(self):
      endog, exog = self.orig_endog, self.orig_exog
      # exog can be None and we could be upcasting one or the other
      if (
          exog is not None
          and (hasattr(endog, "index") and hasattr(exog, "index"))
          and not self.orig_endog.index.equals(self.orig_exog.index)
      ):
          raise ValueError(
              "The indices for endog and exog are not aligned"
          )
      super()._check_integrity()
  
imports: from __future__ import annotations
  from statsmodels.compat.python import lmap
  from functools import reduce
  import numpy
  from pandas import DataFrame, Series, isnull, MultiIndex
  import statsmodels.tools.data
  from statsmodels.tools.decorators import cache_readonly, cache_writable
  from statsmodels.tools.sm_exceptions import MissingDataError
label_desc: Use image node_id 4 for calling the PandasData obj's underlying member method code with example usage: obj._check_integrity() without return types