<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def set_stopextend(self, n):
 """Extend the True elements by n when setting the conditions based on a 'stopcond' condition. n is an integer >= 0. .. note:: Updates the mask if not no_auto. """

        self.conconf.set_condition('stopextend', n)
        if not self.no_auto:
            self.make_mask()