def self_issued(self):
        """
        :return:
            A boolean - if the certificate is self-issued, as defined by RFC
            5280
        """

        if self._self_issued is None:
            self._self_issued = self.subject == self.issuer
        return self._self_issued
def self_issued ( self ) : if self . _self_issued is None : self . _self_issued = self . subject == self . issuer return self . _self_issued
:return:
            A boolean - if the certificate is self-issued, as defined by RFC
            5280