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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: StrOrURL, *, data: Any=None, **kwargs: Any) -> '_RequestContextManager': """Perform HTTP POST request."""

        return _RequestContextManager(
            self._request(hdrs.METH_POST, url,
                          data=data,
                          **kwargs))