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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _make_entity_from_id(entity_cls, entity_obj_or_id, server_config):
 """Given an entity object or an ID, return an entity object. If the value passed in is an object that is a subclass of :class:`Entity`, return that value. Otherwise, create an object of the type that ``field`` references, give that object an ID of ``field_value``, and return that object. :param entity_cls: An :class:`Entity` subclass. :param entity_obj_or_id: Either a :class:`nailgun.entity_mixins.Entity` object or an entity ID. :returns: An ``entity_cls`` object. :rtype: nailgun.entity_mixins.Entity """

    if isinstance(entity_obj_or_id, entity_cls):
        return entity_obj_or_id
    return entity_cls(server_config, id=entity_obj_or_id)