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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 failed(self, group=None, start=0, limit=25):
        '''If no group is provided, this returns a JSON blob of the counts of
        the various types of failures known. If a type is provided, returns
        paginated job objects affected by that kind of failure.'''
        if not group:
            return json.loads(self.client('failed'))
        else:
            results = json.loads(
                self.client('failed', group, start, limit))
            results['jobs'] = self.get(*results['jobs'])
            return results