old_contents: """ Adding attributes additional_time_after_first_section_taxi and 
      additional_time_before_last_section_taxi in table instance
  Revision ID: 52d628e535db
  Revises: 584590c53431
  Create Date: 2019-03-19 14:51:41.599764
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '52d628e535db'
  down_revision = '584590c53431'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      op.add_column(
          'instance', sa.Column('additional_time_after_first_section_taxi', sa.Integer(), nullable=False)
      )
      op.add_column(
          'instance', sa.Column('additional_time_before_last_section_taxi', sa.Integer(), nullable=False)
      )
  
  
  def downgrade():
      op.drop_column('instance', 'additional_time_before_last_section_taxi')
      op.drop_column('instance', 'additional_time_after_first_section_taxi')
  
new_contents: """ Adding attributes additional_time_after_first_section_taxi and 
      additional_time_before_last_section_taxi in table instance
  Revision ID: 52d628e535db
  Revises: 584590c53431
  Create Date: 2019-03-19 14:51:41.599764
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '52d628e535db'
  down_revision = '584590c53431'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      op.add_column(
          'instance', sa.Column('additional_time_after_first_section_taxi', sa.Integer(),
                                nullable=False, server_default='300')
      )
      op.add_column(
          'instance', sa.Column('additional_time_before_last_section_taxi', sa.Integer(),
                                nullable=False, server_default='300')
      )
  
  
  def downgrade():
      op.drop_column('instance', 'additional_time_before_last_section_taxi')
      op.drop_column('instance', 'additional_time_after_first_section_taxi')
  
subject: fix for added attributs for taxi