docs: def _model_foreign(ins):
      """ Get foreign keys info
  
      :type ins: sqlalchemy.orm.mapper.Mapper
      :rtype: list[SaForeignkeyDoc]
      """
      fks = []
      for t in ins.tables:
          fks.extend([
              SaForeignkeyDoc(
                  key=fk.column.key,
                  target=fk.target_fullname,
                  onupdate=fk.onupdate,
                  ondelete=fk.ondelete
              )
              for fk in t.foreign_keys])
      return fks