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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 json(self, dict=None, indent=None):
 """ Returns post JSON representation """

        if not dict:
            dict = self.dict()
        for key, value in dict.iteritems():
            if type(value) == datetime.datetime:
                dict[key] = value.strftime(conf.GOSCALE_ATOM_DATETIME_FORMAT)
        return simplejson.dumps(dict, indent=indent)