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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 validate_timestamp_and_nonce(self, client_key, timestamp, nonce, request, request_token=None, access_token=None):
 """Validates that the nonce has not been used before. :param client_key: The client/consumer key. :param timestamp: The ``oauth_timestamp`` parameter. :param nonce: The ``oauth_nonce`` parameter. :param request_token: Request token string, if any. :param access_token: Access token string, if any. :param request: OAuthlib request. :type request: oauthlib.common.Request :returns: True or False Per `Section 3.3`_ of the spec. "A nonce is a random string, uniquely generated by the client to allow the server to verify that a request has never been made before and helps prevent replay attacks when requests are made over a non-secure channel. The nonce value MUST be unique across all requests with the same timestamp, client credentials, and token combinations." .. _`Section 3.3`: https://tools.ietf.org/html/rfc5849#section-3.3 One of the first validation checks that will be made is for the validity of the nonce and timestamp, which are associated with a client key and possibly a token. If invalid then immediately fail the request by returning False. If the nonce/timestamp pair has been used before and you may just have detected a replay attack. Therefore it is an essential part of OAuth security that you not allow nonce/timestamp reuse. Note that this validation check is done before checking the validity of the client and token.:: nonces_and_timestamps_database = [ (u'foo', 1234567890, u'rannoMstrInghere', u'bar') ] def validate_timestamp_and_nonce(self, client_key, timestamp, nonce, request_token=None, access_token=None):
 return ((client_key, timestamp, nonce, request_token or access_token) not in self.nonces_and_timestamps_database) This method is used by * AccessTokenEndpoint * RequestTokenEndpoint * ResourceEndpoint * SignatureOnlyEndpoint """

        raise self._subclass_must_implement("validate_timestamp_and_nonce")