code: def pack_into(fmt, buf, offset, *args, **kwargs):
      
  
      return CompiledFormat(fmt).pack_into(buf,
                                           offset,
                                           *args,
                                           **kwargs)
docs: Pack given values v1, v2, ... into given bytearray `buf`, starting
      at given bit offset `offset`. Pack according to given format
      string `fmt`. Give `fill_padding` as ``False`` to leave padding
      bits in `buf` unmodified.