def getPlannedFors(self, projectarea_id=None, projectarea_name=None,
                       archived=False, returned_properties=None):
        """Get all :class:`rtcclient.models.PlannedFor` objects by
        project area id or name

        If both `projectarea_id` and `projectarea_name` are None,
        all the plannedfors in all project areas will be returned.

        If no :class:`rtcclient.models.PlannedFor` objecs are retrieved,
        `None` is returned.

        :param projectarea_id: the :class:`rtcclient.project_area.ProjectArea`
            id
        :param projectarea_name: the project area name
        :param archived: (default is False) whether the plannedfors
            are archived
        :param returned_properties: the returned properties that you want.
            Refer to :class:`rtcclient.client.RTCClient` for more explanations
        :return: a :class:`list` that contains all the
            :class:`rtcclient.models.PlannedFor` objects
        :rtype: list
        """

        return self._getPlannedFors(projectarea_id=projectarea_id,
                                    projectarea_name=projectarea_name,
                                    archived=archived,
                                    returned_properties=returned_properties)