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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 get_student_current_grade(self, username, course_id):
 """ Returns an CurrentGrade object for the user in a course Args: username (str):
 an edx user's username course_id (str):
 an edX course id. Returns: CurrentGrade: object representing the student current grade for a course """

        # the request is done in behalf of the current logged in user
        resp = self.requester.get(
            urljoin(
                self.base_url,
                '/api/grades/v1/courses/{course_key}/?username={username}'.format(
                    username=username,
                    course_key=course_id
                )
            )
        )

        resp.raise_for_status()

        return CurrentGrade(resp.json()[0])