code: def validate_name(s: str) -> bool:
      if s.count(".") != 1 or not (0 < s.index(".") < len(s) - 1):
          return False
      if (
          s[0] not in Name.first_char
          or s[s.index(".") + 1] not in Name.first_char
      ):
          return False
      if any((c not in Name.char) for c in s):
          return False
      return True
  
file_path: dstack/src/dstack/_internal/utils/interpolator.py
imports: import string
  from typing import Dict, Iterable, List, Optional, Tuple, Union
label_desc: Use image node_id 3 for calling the VariablesInterpolator obj's underlying member method code with example usage: obj.validate_name(s) and returns: True, False, False, False