old_contents: 
  """Comment assignee type
  
  Revision ID: 504f541411a5
  Revises: 18cbdd3a7fd9
  Create Date: 2015-12-04 13:57:07.047217
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '504f541411a5'
  down_revision = '18cbdd3a7fd9'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
    op.add_column(
        "comments",
        sa.Column("assignee_type", sa.Text(), nullable=True)
    )
  
  
  def downgrade():
    op.drop_column("comments", "assignee_type")
  
new_contents: # Copyright (C) 2015 Google Inc., authors, and contributors <see AUTHORS file>
  # Licensed under http://www.apache.org/licenses/LICENSE-2.0 <see LICENSE file>
  # Created By: ivan@reciprocitylabs.com
  # Maintained By: ivan@reciprocitylabs.com
  
  """Comment assignee type
  
  Revision ID: 504f541411a5
  Revises: 18cbdd3a7fd9
  Create Date: 2015-12-04 13:57:07.047217
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '504f541411a5'
  down_revision = '18cbdd3a7fd9'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
    op.add_column(
        "comments",
        sa.Column("assignee_type", sa.Text(), nullable=True)
    )
  
  
  def downgrade():
    op.drop_column("comments", "assignee_type")
  
subject: Add licence header to migration