code: def percentile_validator(cls, v):
      if re.match(cls.legal_percentile, v):
          return v
      raise ValueError(f"provided `{v}` not in legal percentile format")
  
file_path: FATE/python/fate/components/core/params/_metrics.py
imports: import re
  from typing import Type
  from ._fields import StringChoice, Parameter
label_desc: Use image node_id 2 for calling the LegalPercentile obj's underlying member method code with example usage: obj.percentile_validator(cls, v) and returns: v