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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 set_flag(self, value, flag, reset_val=False):
 """Set a flag to 0 if the corresponding value is 0"""

        if not self.__dict__[flag]:
            self.__dict__[flag] = matrix(1.0, (len(self.__dict__[value]), 1),
                                         'd')
        for idx, item in enumerate(self.__dict__[value]):
            if item == 0:
                self.__dict__[flag][idx] = 0
                if reset_val:
                    self.__dict__[value][idx] = 1