op.create_table('team', sa.Column('id', sa.Integer(), nullable=False), sa.Column('name', sa.String(), nullable=False), sa.Column('headquarters', sa.String(), nullable=True), sa.PrimaryKeyConstraint('id') ) op.add_column('hero', sa.Column('team_id', sa.Integer(), nullable=True)) op.create_foreign_key('fk_hero_team_id', 'hero', 'team', ['team_id'], ['id'])