ó øĒTQc@sšdZdefd„ƒYZdefd„ƒYZdefd„ƒYZdefd„ƒYZd efd „ƒYZd efd „ƒYZd efd„ƒYZdefd„ƒYZ dS(s> Classes to represent the definitions of aggregate functions. t AggregatecBs5eZdZd„Zd„ZeeƒZd„ZRS(s' Default Aggregate definition. cKs||_||_dS(s6Instantiate a new aggregate. * lookup is the field on which the aggregate operates. * extra is a dictionary of additional data to provide for the aggregate definition Also utilizes the class variables: * name, the identifier for this aggregate function. N(tlookuptextra(tselfRR((s4../Django//lib/python/django/db/models/aggregates.pyt__init__ s cCsd|j|jjƒfS(Ns%s__%s(Rtnametlower(R((s4../Django//lib/python/django/db/models/aggregates.pyt_default_aliasscCsDt|j|jƒ}||d|d||j}||j|s+