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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 verify_keys(self):
 """Verify that the public and private key combination is valid; raises MollomAuthenticationError otherwise"""

        verify_keys_endpoint = Template("${rest_root}/site/${public_key}")
        url = verify_keys_endpoint.substitute(rest_root=self._rest_root, public_key=self._public_key)
        
        data = { "clientName": "mollom_python", "clientVersion": "1.0" }

        self._client.headers["Content-Type"] = "application/x-www-form-urlencoded"

        response = self._client.post(url, data, timeout=self._timeout)
        if response.status_code != 200:
            raise MollomAuthenticationError

        return True