code: def upgrade():
      op.add_column(
          "table_columns",
          sa.Column(
              "python_date_format", sa.String(length=255), nullable=True
          ),
      )
      op.add_column(
          "table_columns",
          sa.Column(
              "database_expression",
              sa.String(length=255),
              nullable=True,
          ),
      )
  
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