old_contents: # vim: tabstop=4 shiftwidth=4 softtabstop=4
  #
  # Copyright (c) 2012 Canonical Ltd.
  # All Rights Reserved.
  #
  #    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.
  
  from sqlalchemy import select, Column, Table, MetaData, String, DateTime
  
  
  def upgrade(migrate_engine):
      meta = MetaData()
      meta.bind = migrate_engine
  
      volumes = Table('volumes', meta, autoload=True)
      attach_datetime = Column('attachtime_datetime', DateTime(timezone=False))
      attach_datetime.create(volumes)
  
      old_attachtime = volumes.c.attach_time
  
      try:
          volumes_list = list(volumes.select().execute())
          for v in volumes_list:
              attach_time = select([volumes.c.attach_time],
                  volumes.c.id == v['id'])
              volumes.update().\
                  where(volumes.c.id == v['id']).\
                  values(attach_datetime=attach_time).execute()
      except Exception:
          attach_datetime.drop()
          raise
  
      old_attachtime.alter(name='attach_time_old')
      attach_datetime.alter(name='attach_time')
      old_attachtime.drop()
  
  
  def downgrade(migrate_engine):
      meta = MetaData()
      meta.bind = migrate_engine
  
      volumes = Table('volumes', meta, autoload=True)
      attach_string = Column('attachtime_string', String(255))
      attach_string.create(volumes)
  
      old_attachtime = volumes.c.attach_time
  
      try:
          volumes_list = list(volumes.select().execute())
          for v in volumes_list:
              attach_time = select([volumes.c.attach_time],
                  volumes.c.id == v['id'])
              volumes.update().\
                  where(volumes.c.id == v['id']).\
                  values(attach_string=attach_time).execute()
      except Exception:
          attach_datetime.drop()
          raise
  
      old_attachtime.alter(name='attach_time_old')
      attach_string.alter(name='attach_time')
      old_attachtime.drop()
  
new_contents: # vim: tabstop=4 shiftwidth=4 softtabstop=4
  #
  # Copyright (c) 2012 Canonical Ltd.
  # All Rights Reserved.
  #
  #    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.
  
  from sqlalchemy import select, Column, Table, MetaData, String, DateTime
  
  
  def upgrade(migrate_engine):
      meta = MetaData()
      meta.bind = migrate_engine
  
      volumes = Table('volumes', meta, autoload=True)
      attach_datetime = Column('attachtime_datetime', DateTime(timezone=False))
      attach_datetime.create(volumes)
  
      old_attachtime = volumes.c.attach_time
  
      try:
          volumes_list = list(volumes.select().execute())
          for v in volumes_list:
              attach_time = select([volumes.c.attach_time],
                  volumes.c.id == v['id'])
              volumes.update().\
                  where(volumes.c.id == v['id']).\
                  values(attach_datetime=attach_time).execute()
      except Exception:
          attach_datetime.drop()
          raise
  
      old_attachtime.alter(name='attach_time_old')
      attach_datetime.alter(name='attach_time')
      old_attachtime.drop()
  
  
  def downgrade(migrate_engine):
      meta = MetaData()
      meta.bind = migrate_engine
  
      volumes = Table('volumes', meta, autoload=True)
      attach_string = Column('attachtime_string', String(255))
      attach_string.create(volumes)
  
      old_attachtime = volumes.c.attach_time
  
      try:
          volumes_list = list(volumes.select().execute())
          for v in volumes_list:
              attach_time = select([volumes.c.attach_time],
                  volumes.c.id == v['id'])
              volumes.update().\
                  where(volumes.c.id == v['id']).\
                  values(attach_string=attach_time).execute()
      except Exception:
          attach_string.drop()
          raise
  
      old_attachtime.alter(name='attach_time_old')
      attach_string.alter(name='attach_time')
      old_attachtime.drop()
  
subject: Fix column variable typo