code: def process_env_var(env_var: str) -> Variable:
      if env_var in (
          "platform_python_implementation",
          "python_implementation",
      ):
          return Variable("platform_python_implementation")
      else:
          return Variable(env_var)
  
imports: import ast
  from typing import Any, List, NamedTuple, Optional, Tuple, Union
  from ._tokenizer import DEFAULT_RULES, Tokenizer
label_desc: Use image node_id 15 for calling a global function with example usage: process_env_var(env_var) and returns: Variable, Variable