code: def upgrade() -> None:
      bind = op.get_bind()
  
      if bind.dialect.name == "postgresql":
          op.execute(
              "ALTER TYPE suggestion_type_enum ADD VALUE IF NOT EXISTS 'model';"
          )
          op.execute(
              "ALTER TYPE suggestion_type_enum ADD VALUE IF NOT EXISTS 'human';"
          )
  
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