new_contents: """fix the type of the updated_at column for shelters
  
  Revision ID: 953c5e0cebad
  Revises: 9bfedc780ac5
  Create Date: 2016-06-17 09:00:35.875583
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '953c5e0cebad'
  down_revision = '9bfedc780ac5'
  branch_labels = None
  depends_on = None
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      op.drop_column('shelter', 'updated_at')
      op.add_column('shelter', sa.Column('updated_at', sa.DateTime(),
                      default=datetime.now))
  
  
  def downgrade():
      op.drop_column('shelter', 'updated_at')
      op.add_column('shelter', sa.Column('updated_at', sa.Boolean(),
                      default=datetime.now))
  
subject: Add alembic script to fix the type of the column updated_at of shelters