code: def visitalias(self, node):
      name = node.asname if node.asname else node.name
  
      if "." in name:
          name = name.split(".", 1)[0]
  
      if ast.Store in self.ctx_types:
          return {name}
      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 4 for calling the SymbolVisitor obj's underlying member method code with example usage: obj.visitalias(node) and returns: unknown, set