text: """empty message
  
  Revision ID: 3f17791e2f9e
  Revises: 
  Create Date: 2019-04-03 15:29:47.450861
  
  """
  from alembic import op
  import sqlalchemy as sa
  
  
  # revision identifiers, used by Alembic.
  revision = '3f17791e2f9e'
  down_revision = None
  branch_labels = None
  depends_on = None
  
  
  def upgrade():
      # ### commands auto generated by Alembic - please adjust! ###
      op.create_table('cities',
      sa.Column('id', sa.Integer(), nullable=False),
      sa.Column('city_name', sa.String(length=256), nullable=True),
      sa.Column('date_created', sa.DateTime(), nullable=True),
      sa.PrimaryKeyConstraint('id')
      )
      op.create_index(op.f('ix_cities_city_name'), 'cities', ['city_name'], unique=True)
      # ### end Alembic commands ###
  
  
  def downgrade():
      # ### commands auto generated by Alembic - please adjust! ###
      op.drop_index(op.f('ix_cities_city_name'), table_name='cities')
      op.drop_table('cities')
      # ### end Alembic commands ###
  