Checks if the x509 certs of the SP exists and are valid.
        :returns: If the x509 certs of the SP exists and are valid
        :rtype: boolean

def check_sp_certs(self):
        """
        Checks if the x509 certs of the SP exists and are valid.
        :returns: If the x509 certs of the SP exists and are valid
        :rtype: boolean
        """
        key = self.get_sp_key()
        cert = self.get_sp_cert()
        return key is not None and cert is not None