new_contents: """add x,y to markers
  
  Revision ID: 20f14f4f1de7
  Revises: 21b54c24a2c8
  Create Date: 2018-10-01 23:27:21.307860
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '20f14f4f1de7'
  down_revision = '21b54c24a2c8'
  branch_labels = None
  depends_on = None
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.add_column('markers', sa.Column('x', sa.Float(), nullable=True))
      op.add_column('markers', sa.Column('y', sa.Float(), nullable=True))
      ### end Alembic commands ###
  
  
  def downgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.drop_column('markers', 'y')
      op.drop_column('markers', 'x')
      ### end Alembic commands ###
  
subject: add x and y alembic revision