docs: def has(self, querypart_name, value=None):
          """Returns True if `querypart_name` with `value` is set.
  
          For example you can check if you already used condition by `sql.has('where')`.
  
          If you want to check for more information, for example if that condition
          also contain ID, you can do this by `sql.has('where', 'id')`.
          """
          querypart = self._queryparts.get(querypart_name)
          if not querypart:
              return False
          if not querypart.is_set:
              return False
          if value:
              return querypart.has(value)
          return True