code: def upgrade():
      with op.batch_alter_table("dashboards") as batch_op:
          batch_op.add_column(
              sa.Column("published", sa.Boolean(), nullable=True)
          )
      op.execute("UPDATE dashboards SET published='1'")
  
imports: import sqlalchemy
  from alembic import op
label_desc: Use image node_id 1 for calling a global function with example usage: upgrade() without return types