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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 __normalize_grades(self):
 """ Adjust the grades list. If a grade has been set, set All to false """


        if 'grades' in self and self['grades']['All'] is True:
            for grade in self['grades']:
                if grade != 'All' and self['grades'][grade] is True:
                    self['grades']['All'] = False
                    break