code: def setBody(self, body_string):
      self._body = body_string
      self._length = len(body_string)
  
imports: import struct
  from mindsdb.api.mysql.mysql_proxy.libs.constants.mysql import MAX_PACKET_SIZE
  from mindsdb.utilities import log
label_desc: Use image node_id 4 for calling the Packet obj's underlying member method code with example usage: obj.setBody(body_string) without return types