class_docstr: Pattern for a mutable list-like object shareable via a shared
  memory block.  It differs from the built-in list type in that these
  lists can not change their overall length (i.e. no append, insert,
  etc.)
  
  Because values are packed into a memoryview as bytes, the struct
  packing format for any storable value must require no more than 8
  characters to describe its format.
docstr: Sets the packing format and back transformation code for a
  single value in the list at the specified position.
code: def _set_packing_format_and_transform(
      self, position, fmt_as_str, value
  ):
      """Sets the packing format and back transformation code for a
      single value in the list at the specified position."""
  
      if (position >= self._list_len) or (self._list_len < 0):
          raise IndexError("Requested position out of range.")
  
      struct.pack_into(
          "8s",
          self.shm.buf,
          self._offset_packing_formats + position * 8,
          fmt_as_str.encode(_encoding),
      )
  
      transform_code = self._extract_recreation_code(value)
      struct.pack_into(
          "b",
          self.shm.buf,
          self._offset_back_transform_codes + position,
          transform_code,
      )
  
imports: from functools import partial
  import mmap
  import os
  import errno
  import struct
  import secrets
  import types
  from .None import resource_tracker
label_desc: Use image node_id 5 for calling the ShareableList obj's underlying member method code with example usage: obj._set_packing_format_and_transform(position, fmt_as_str, value) without return types