docstr: Raise exception to signal syntax error in regexp.
docstr_tok: ["Raise","exception","to","signal","syntax","error","in","regexp","."]
code: def error(self, mess):
      """Raise exception to signal syntax error in regexp."""
      raise RegexpSyntaxError(
          "Syntax error in regexp %s at position %d: %s"
          % (repr(self.s), self.i, mess)
      )
  
file_path: catboost/contrib/tools/cython/Cython/Plex/Traditional.py
imports: from __future__ import absolute_import
  from .Regexps import Alt, Seq, Rep, Rep1, Opt, Any, AnyBut, Bol, Eol, Char
  from .Errors import PlexError
label_desc: Use image node_id 12 for calling the REParser obj's underlying member method code with example usage: obj.error(mess) without return types