code: def visitName(self, node):
      if isinstance(node.ctx, self.ctx_types):
          return {node.id}
      else:
          return set()
  
file_path: turicreate/src/python/turicreate/meta/asttools/visitors/symbol_visitor.py
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  from ...asttools.visitors import Visitor
  import ast
label_desc: Use image node_id 3 for calling the SymbolVisitor obj's underlying member method code with example usage: obj.visitName(node) and returns: unknown, set