code: def find_assign(node):
      if node.type == syms.expr_stmt:
          return node
      if node.type == syms.simple_stmt or node.parent is None:
          return None
      return find_assign(node.parent)
  
file_path: catboost/contrib/tools/python/src/Lib/lib2to3/fixes/fix_next.py
imports: from ..pgen2 import token
  from ..pygram import python_symbols
  from ..None import fixer_base
  from ..fixer_util import Name, Call, find_binding
label_desc: Use image node_id 2 for calling a global function with example usage: find_assign(node) and returns: find_assign, node, None