text: """add an email field
  
  Revision ID: c9ad6a066edf
  Revises: 667c4bbf3aee
  Create Date: 2019-09-15 13:57:50.448893
  
  """
  from alembic import op
  import sqlalchemy as sa
  
  
  # revision identifiers, used by Alembic.
  revision = 'c9ad6a066edf'
  down_revision = '667c4bbf3aee'
  branch_labels = None
  depends_on = None
  
  
  def upgrade():
      # ### commands auto generated by Alembic - please adjust! ###
      op.add_column('users', sa.Column('email', sa.String(length=255), nullable=True))
      op.create_index(op.f('ix_users_email'), 'users', ['email'], unique=True)
      op.create_index(op.f('ix_users_username'), 'users', ['username'], unique=False)
      # ### end Alembic commands ###
  
  
  def downgrade():
      # ### commands auto generated by Alembic - please adjust! ###
      op.drop_index(op.f('ix_users_username'), table_name='users')
      op.drop_index(op.f('ix_users_email'), table_name='users')
      op.drop_column('users', 'email')
      # ### end Alembic commands ###
  