class_docstr: Replacer class for replacing HLO instructions by FileCheck captures.
code: def _generate_unique_varname(self, instr_name: str) -> str:
      self._counter += 1
      normalized_instr_name = ESCAPE_FILECHECK_VARNAME.sub(
          "_", instr_name.replace("%", "")
      )
      return f"{normalized_instr_name}_{self._counter}"
  
file_path: tensorflow/third_party/xla/xla/service/generate_test_hlo_checks.py
imports: import re
  import shutil
  import sys
  import tempfile
  from typing import Dict
label_desc: Use image node_id 4 for calling the FileCheckVarReplacer obj's underlying member method code with example usage: obj._generate_unique_varname(instr_name) and returns: normalized_instr_name, str, self