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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 delta_crl_distribution_points(self):
 """ Returns delta CRL URLs - only applies to complete CRLs :return: A list of zero or more DistributionPoint objects """


        if self._delta_crl_distribution_points is None:
            self._delta_crl_distribution_points = []

            if self.freshest_crl_value is not None:
                for distribution_point in self.freshest_crl_value:
                    distribution_point_name = distribution_point['distribution_point']
                    # RFC 5280 indicates conforming CA should not use the relative form
                    if distribution_point_name.name == 'name_relative_to_crl_issuer':
                        continue
                    # This library is currently only concerned with HTTP-based CRLs
                    for general_name in distribution_point_name.chosen:
                        if general_name.name == 'uniform_resource_identifier':
                            self._delta_crl_distribution_points.append(distribution_point)

        return self._delta_crl_distribution_points