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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 validiate_webhook_signature(self, webhook, signature):
 """Validates a webhook signature from a webhook body + client secret Parameters webhook (string) The request body of the webhook. signature (string) The webhook signature specified in X-Uber-Signature header. """

        digester = hmac.new(self.session.oauth2credential.client_secret,
                            webhook,
                            hashlib.sha256
                            )
        return (signature == digester.hexdigest())