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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 _authenticate(self):
 """ Perform an authentication against NetMRI"""

        url = "{base_url}/api/authenticate".format(base_url=self._base_url())
        data = json.dumps({'username': self.username, "password": self.password})
        # Bypass authentication check in make_request by using _send_request
        logger.debug("Authenticating against NetMRI")
        self._send_request(url, method="post", data=data)
        self._is_authenticated = True