code: def _is_ast_str(node):
      """Determine whether this node represents a string."""
      allowed_types = [ast.Str]
      if hasattr(ast, "Bytes"):
          allowed_types += [ast.Bytes]
      if hasattr(ast, "JoinedStr"):
          allowed_types += [ast.JoinedStr]
      if hasattr(ast, "FormattedValue"):
          allowed_types += [ast.FormattedValue]
      return isinstance(node, allowed_types)
  
imports: import ast
  import copy
  import functools
  import sys
  import pasta
  from tensorflow.tools.compatibility import all_renames_v2
  from tensorflow.tools.compatibility import ast_edits
  from tensorflow.tools.compatibility import module_deprecations_v2
  from tensorflow.tools.compatibility import reorders_v2
label_desc: Use image node_id 1 for calling a global function with example usage: _is_ast_str(node) and returns: isinstance