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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 _resolve_method(self, request):
 # type: (ApiClientRequest) -> Callable """Resolve the method from request object to `requests` http call. :param request: Request to dispatch to the ApiClient :type request: ApiClientRequest :return: The HTTP method that maps to the request call. :rtype: Callable :raises :py:class:`ask_sdk_core.exceptions.ApiClientException` if invalid http request method is being called """

        try:
            return getattr(requests, request.method.lower())
        except AttributeError:
            raise ApiClientException(
                "Invalid request method: {}".format(request.method))