old_contents: from neomodel import (StructuredNode, StringProperty, IntegerProperty, ArrayProperty,
      RelationshipTo, RelationshipFrom)
  
  # Create your models here.
  
  class Article(StructuredNode):
      title = StringProperty()
      journal = StringProperty()
      year = IntegerProperty()
      volume = IntegerProperty()
      authors = RelationshipFrom('Author', 'AUTHORED')
  
  
  class Author(StructuredNode):
      name = StringProperty()
      articles = RelationshipTo('Article', 'AUTHORED')
      def __str__(self):
          # Call str function here since sometimes the object might not
          # found in the database...
          # Python sucks
          return "<Author: " + str(self.name) + ">"
      def __repr__(self):
          return "<Author: " + repr(self.name) + ">"
  
      def __hash__(self):
          """
          We use name of the author as the hash value
          """
          return hash(self.name)
      def __cmp__(self, other):
          return cmp(self.name, other.name)
  
      def toDict(self):
          return {
              "name": self.name
          }
  
new_contents: from neomodel import (StructuredNode, StringProperty, IntegerProperty, ArrayProperty,
      RelationshipTo, RelationshipFrom)
  
  # Create your models here.
  
  class Article(StructuredNode):
      title = StringProperty()
      journal = StringProperty()
      year = IntegerProperty()
      volume = StringProperty()
      authors = RelationshipFrom('Author', 'AUTHORED')
  
  
  class Author(StructuredNode):
      name = StringProperty()
      articles = RelationshipTo('Article', 'AUTHORED')
      def __str__(self):
          # Call str function here since sometimes the object might not
          # found in the database...
          # Python sucks
          return "<Author: " + str(self.name) + ">"
      def __repr__(self):
          return "<Author: " + repr(self.name) + ">"
  
      def __hash__(self):
          """
          We use name of the author as the hash value
          """
          return hash(self.name)
      def __cmp__(self, other):
          return cmp(self.name, other.name)
  
      def toDict(self):
          return {
              "name": self.name
          }
  
subject: Fix bug in class Article, volume should be string type