code: def str_pack_len(self, str):
      return int((self.str_raw_len(str) + 3) / 4) * 4
  
imports: from google.protobuf.descriptor import FieldDescriptor
  from utils.util import mace_check
  import sys
  import struct
  import tempfile
label_desc: Use image node_id 3 for calling the ProtoConverter obj's underlying member method code with example usage: obj.str_pack_len(str) and returns: unknown