old_contents: #!/usr/bin/python2.5
  #
  # Copyright 2008 the Melange authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #   http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  """Helpers functions for updating different kinds of models in datastore.
  """
  
  __authors__ = [
    '"Pawel Solyga" <pawel.solyga@gmail.com>',
    ]
  
  from google.appengine.ext import db
  
  def updateModelProperties(model, **model_properties):
    """Update existing model entity using supplied model properties.
  
    Args:
      model: a model entity
      **model_properties: keyword arguments that correspond to model entity
        properties and their values
  
    Returns:
      the original model entity with any supplied properties changed 
    """
    def update():
      return _unsafeUpdateModelProperties(model, **model_properties)
  
    return db.run_in_transaction(update)
  
  
  def _unsafeUpdateModelProperties(model, **model_properties):
    """(see updateModelProperties)
  
    Like updateModelProperties(), but not run within a transaction. 
    """
    properties = model.properties()
  
    for prop in properties.values():
      if prop.name in model_properties:
        value = model_properties[prop.name]
        prop.__set__(model, value)
  
    model.put()
    return model
new_contents: #!/usr/bin/python2.5
  #
  # Copyright 2008 the Melange authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #   http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  """Helpers functions for updating different kinds of models in datastore.
  """
  
  __authors__ = [
    '"Pawel Solyga" <pawel.solyga@gmail.com>',
    ]
  
  from google.appengine.ext import db
  
  
  def updateModelProperties(model, **model_properties):
    """Update existing model entity using supplied model properties.
  
    Args:
      model: a model entity
      **model_properties: keyword arguments that correspond to model entity
        properties and their values
  
    Returns:
      the original model entity with any supplied properties changed 
    """
    def update():
      return _unsafeUpdateModelProperties(model, **model_properties)
  
    return db.run_in_transaction(update)
  
  
  def _unsafeUpdateModelProperties(model, **model_properties):
    """(see updateModelProperties)
  
    Like updateModelProperties(), but not run within a transaction. 
    """
    properties = model.properties()
  
    for prop in properties.values():
      if prop.name in model_properties:
        value = model_properties[prop.name]
        prop.__set__(model, value)
  
    model.put()
    return model
subject: Fix missing blank line to follow PythonStyleGuide in model.py.