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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:
 async def post(self, cmd, data=None, timeout=None, **args):
 """Perform DAAP POST command with optional data."""

        def _post_request():
            headers = copy(_DMAP_HEADERS)
            headers['Content-Type'] = 'application/x-www-form-urlencoded'
            return self.http.post_data(
                self._mkurl(cmd, *args),
                data=data,
                headers=headers,
                timeout=timeout)

        await self._assure_logged_in()
        return await self._do(_post_request)