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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 _format(self, method="sparql", dt_format="turtle"):
 """ Rormats the value in various formats args: method: ['sparql', 'json', 'pyuri'] dt_format: ['turtle','uri'] used in conjuction with the 'sparql' method """


        try:
            return __FORMAT_OPTIONS__[method](self, dt_format=dt_format)
        except KeyError:
            raise NotImplementedError("'{}' is not a valid format method"
                                      "".format(method))