code: def determine_variable_usage(root, args, symbols, closure_vars):
      """The helper function for calling the dedicated visitor."""
      visitor = PyVariableUsage(args, symbols, closure_vars)
      visitor.visit(root)
      return visitor.status
  
file_path: tvm/python/tvm/te/hybrid/preprocessor.py
imports: import ast
  import sys
  from .runtime import HYBRID_GLOBALS
  from .utils import _internal_assert
label_desc: Use image node_id 1 for calling a global function with example usage: determine_variable_usage(root, args, symbols, closure_vars) and returns: visitor