code: def read_authentication(self, encoding=None):
      try:
          auth_type = self.read_byte()
      except PostgresEmptyDataException:
          # No authentication parameters specified. Which is fine if we're local on a mindsdbuser
          return ""
      try:
          auth_type = PostgresAuthType(auth_type)
      except Exception as e:
          raise UnsupportedPostgresAuthException(e)
      if auth_type not in self.supported_auth_types:
          raise UnsupportedPostgresAuthException(
              "%s is not a supported auth type identifier" % auth_type
          )
      length = self.read_int32()
      password = strip_null_byte(
          self.read_bytes(length - 4), encoding=encoding
      )  # password. Do something with later. We read to clear buffer.
      return password
  
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 11 for calling the PostgresPacketReader obj's underlying member method code with example usage: obj.read_authentication(encoding) and returns: password, str