docstr: Generate argument unpacking code.
  
  arg is the function argument to be unpacked (a string), and
  unpackto is a list or nested lists of the variable names (strings) to
  unpack to.
docstr_tok: ["Generate","argument","unpacking","code",".","arg","is","the","function","argument","to","be","unpacked","(","a","string",")",",","and","unpackto","is","a","list","or","nested","lists","of","the","variable","names","(","strings",")","to","unpack","to","."]
code: def _print_unpacking(self, unpackto, arg):
      """Generate argument unpacking code.
  
      arg is the function argument to be unpacked (a string), and
      unpackto is a list or nested lists of the variable names (strings) to
      unpack to.
      """
  
      def unpack_lhs(lvalues):
          return "[{}]".format(
              ", ".join(
                  unpack_lhs(val) if iterable(val) else val
                  for val in lvalues
              )
          )
  
      return ["{} = {}".format(unpack_lhs(unpackto), arg)]
  
imports: from __future__ import annotations
  from typing import Any
  import builtins
  import inspect
  import keyword
  import textwrap
  import linecache
  from sympy.external import import_module
  from sympy.utilities.exceptions import sympy_deprecation_warning
  from sympy.utilities.decorator import doctest_depends_on
  from sympy.utilities.iterables import is_sequence, iterable, NotIterable, flatten
  from sympy.utilities.misc import filldedent
label_desc: Use image node_id 7 for calling the _EvaluatorPrinter obj's underlying member method code with example usage: obj._print_unpacking(unpackto, arg) and returns: list, str