text: # Copyright (c) Microsoft Corporation.
  # Licensed under the MIT license.
  
  
  class Graph(object):
      def __init__(self):
          self.entities = []
          self.entity_type_sizes = []
          self.relations = None
          self.relation_size = 0
  
      def clear(self):
          self.entities = []
  
  
  class Entity(object):
      def __init__(self, type, row, col):
          self.data = None
          self.type = type
          self.age = None
          # The following should not be used directly by the agent.
          # It's used by the environment in assembling the observation.
          self.row = row
          self.col = col
  