old_contents: """add last_modified column for events
  
  Revision ID: 54dcea22a268
  Revises: 41f957b595fc
  Create Date: 2015-03-16 23:15:55.908307
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '54dcea22a268'
  down_revision = '41f957b595fc'
  
  from alembic import op
  from sqlalchemy.sql import text
  import sqlalchemy as sa
  
  
  def upgrade():
      conn = op.get_bind()
      conn.execute(text("set @@lock_wait_timeout = 20;"))
      conn.execute(text("ALTER TABLE event ADD COLUMN last_modified DATETIME"))
  
  
  def downgrade():
      conn = op.get_bind()
      conn.execute(text("set @@lock_wait_timeout = 20;"))
      conn.execute(text("ALTER TABLE event DROP COLUMN last_modified"))
  
new_contents: """add last_modified column for events
  
  Revision ID: 54dcea22a268
  Revises: 486c7fa5b533
  Create Date: 2015-03-16 23:15:55.908307
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '54dcea22a268'
  down_revision = '486c7fa5b533'
  
  from alembic import op
  from sqlalchemy.sql import text
  import sqlalchemy as sa
  
  
  def upgrade():
      conn = op.get_bind()
      conn.execute(text("set @@lock_wait_timeout = 20;"))
      conn.execute(text("ALTER TABLE event ADD COLUMN last_modified DATETIME"))
  
  
  def downgrade():
      conn = op.get_bind()
      conn.execute(text("set @@lock_wait_timeout = 20;"))
      conn.execute(text("ALTER TABLE event DROP COLUMN last_modified"))
  
subject: Undo revision changes to previous migration