class_docstr: Finds the longest form of variable names and their imports in code
  
  Only retains names from imported modules.
code: def visit_Import(self, node, prefix=""):
      for alias in node.names:
          local_name = alias.asname or alias.name
          self.imported_names[local_name] = prefix + alias.name
  
file_path: tensorly/doc/sphinx_ext/sphinx_gallery/backreferences.py
imports: from __future__ import print_function
  import ast
  import os
label_desc: Use image node_id 2 for calling the NameFinder obj's underlying member method code with example usage: obj.visit_Import(node, prefix) without return types