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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 _post(self, url, **kw):
        '''
        Makes a POST request, setting Authorization
        header by default
        '''
        headers = kw.pop('headers', {})
        headers.setdefault('Authorization', self.AUTHORIZATION_HEADER)
        kw['headers'] = headers
        resp = self.session.post(url, **kw)
        self._raise_for_status(resp)
        return resp