old_contents: """Create announcement table
  
  Revision ID: ca9164362ca2
  Revises: 920578f0de9c
  Create Date: 2017-05-26 12:55:21.180329
  
  """
  
  # revision identifiers, used by Alembic.
  revision = 'ca9164362ca2'
  down_revision = '920578f0de9c'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def make_timestamp():
      now = datetime.datetime.utcnow()
      return now.isoformat()
  
  
  def upgrade():
      op.create_table(
          'announcement',
          sa.Column('id', sa.Integer, primary_key=True),
          sa.Column('title', sa.Unicode(length=255), nullable=False),
          sa.Column('body', sa.UnicodeText, nullable=False),
          sa.Column('user_id', sa.Integer, sa.ForeignKey('user.id')),
          sa.Column('created', sa.Text, default=make_timestamp),
      )
  
  def downgrade():
      op.drop_table('announcement')
new_contents: """Create announcement table
  
  Revision ID: ca9164362ca2
  Revises: 920578f0de9c
  Create Date: 2017-05-26 12:55:21.180329
  
  """
  
  # revision identifiers, used by Alembic.
  revision = 'ca9164362ca2'
  down_revision = '38ac962bf24d'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def make_timestamp():
      now = datetime.datetime.utcnow()
      return now.isoformat()
  
  
  def upgrade():
      op.create_table(
          'announcement',
          sa.Column('id', sa.Integer, primary_key=True),
          sa.Column('title', sa.Unicode(length=255), nullable=False),
          sa.Column('body', sa.UnicodeText, nullable=False),
          sa.Column('user_id', sa.Integer, sa.ForeignKey('user.id')),
          sa.Column('created', sa.Text, default=make_timestamp),
      )
  
  def downgrade():
      op.drop_table('announcement')
subject: fix alembic down revision head