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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 dump_json(self, pretty=True):
 """ Return a string representation of this CloudFormation template. """

        # Build template
        t = {}
        t['AWSTemplateFormatVersion'] = '2010-09-09'        
        if self.description is not None:
            t['Description'] = self.description
        self.elements.dump_to_template_obj(self, t)

        return _CustomJSONEncoder(indent=2 if pretty else None,
                                  sort_keys=False).encode(t)