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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 create_missing(self):
 """Possibly set several extra instance attributes. If ``onthefly_register`` is set and is true, set the following instance attributes: * account_password * account_firstname * account_lastname * attr_login * attr_mail """

        super(AuthSourceLDAP, self).create_missing()
        if getattr(self, 'onthefly_register', False) is True:
            for field in (
                    'account_password',
                    'attr_firstname',
                    'attr_lastname',
                    'attr_login',
                    'attr_mail'):
                if not hasattr(self, field):
                    setattr(self, field, self._fields[field].gen_value())