code: def decrypt_assertions(self, encrypted_assertions, decr_txt, issuer=None,
              verified=False):
          
          res = []
          for encrypted_assertion in encrypted_assertions:
              if encrypted_assertion.extension_elements:
                  assertions = extension_elements_to_elements(
                      encrypted_assertion.extension_elements, [saml, samlp])
                  for assertion in assertions:
                      if assertion.signature and not verified:
                          if not self.sec.check_signature(
                                  assertion, origdoc=decr_txt,
                                  node_name=class_name(assertion), issuer=issuer):
                              logger.error("Failed to verify signature on '%s'",
                                           assertion)
                              raise SignatureError()
                      res.append(assertion)
          return res
docs: Moves the decrypted assertion from the encrypted assertion to a
          list.
  
          :param encrypted_assertions: A list of encrypted assertions.
          :param decr_txt: The string representation containing the decrypted
          data. Used when verifying signatures.
          :param issuer: The issuer of the response.
          :param verified: If True do not verify signatures, otherwise verify
          the signature if it exists.
          :return: A list of decrypted assertions.