old_contents: from datetime import datetime
  
  class Base(object):
    def load(self, data):
      for name, value in data.items():
        if hasattr(self, name):
          setattr(self, name, value)
  
      return self
  
    def value_to_time(self, value):
      if value != None:
        return datetime.strptime(value, '%Y-%m-%dT%H:%M:%S+00:00')
  
new_contents: from datetime import datetime
  
  class Base(object):
    def load(self, data):
      for name, value in list(data.items()):
        if hasattr(self, name):
          setattr(self, name, value)
  
      return self
  
    def value_to_time(self, value):
      if value != None:
        return datetime.strptime(value, '%Y-%m-%dT%H:%M:%S+00:00')
  
subject: Update dict.items() for Python 3 compatibility