code: def read_int32(self):
      data = self.read_bytes(4)
      return struct.unpack("!i", data)[0]
  
imports: import struct
  from typing import List, Any, BinaryIO, Sequence, Dict
  from mindsdb.api.postgres.postgres_proxy.utilities import strip_null_byte
  from mindsdb.utilities import log
  import time
  from mindsdb.api.postgres.postgres_proxy.postgres_packets.postgres_fields import PostgresField
  from mindsdb.api.postgres.postgres_proxy.postgres_packets.postgres_message_identifiers import PostgresBackendMessageIdentifier, PostgresFrontendMessageIdentifier, PostgresAuthType
label_desc: Use image node_id 7 for calling the PostgresPacketReader obj's underlying member method code with example usage: obj.read_int32() and returns: struct