<s> from django . db import models <EOL> from datetime import datetime <EOL> def expensive_calculation ( ) : <EOL> expensive_calculation . num_runs += <NUM_LIT:1> <EOL> return datetime . now ( ) <EOL> class Poll ( models . Model ) : <EOL> question = models . CharField ( max_length = <NUM_LIT:200> ) <EOL> answer = models . CharField ( max_length = <NUM_LIT:200> ) <EOL> pub_date = models . DateTimeField ( '<STR_LIT>' , default = expensive_calculation ) </s>
