text: from mongoengine import Document, EmbeddedDocument, connect
  from mongoengine.fields import (
      DateTimeField,
      EmbeddedDocumentField,
      ListField,
      ReferenceField,
      StringField,
      DictField,
      IntField,
      URLField,
      BinaryField,
      BooleanField,
      DynamicField,
      FloatField,
      UUIDField
  )
  
  class Table(Document):
  
      table = IntField()
      state = IntField()
  
  
  class Session(Document):
  
      sessionId = UUIDField()
      sessionStart = DateTimeField()
      sessionEnd = DateTimeField()
      states = ListField()
      tableId = IntField()
  
  
  class Collection(Document):
      fsr_status = IntField()
      timestamp = DateTimeField()
      rfid_status = IntField()
  
  
  # class TrayIn(Document):
  #     fsr_status = IntField()
  #     timestamp = DateTimeField()
  #     rfid_status = IntField()
  
  