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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 _send_remote(self, url, data, headers=None, callback=None):
 """ Initialise a Tornado AsyncClient and send the request to the sentry server. If the callback is a callable, it will be called with the response. """

        if headers is None:
            headers = {}

        return AsyncHTTPClient().fetch(
            url, callback, method="POST", body=data, headers=headers,
            validate_cert=self.validate_cert
        )