def get_student_certificate(self, username, course_id):
        """
        Returns an Certificate object with the user certificates

        Args:
            username (str): an edx user's username
            course_id (str): an edX course id.

        Returns:
            Certificate: object representing the student certificate for a course
        """
        # the request is done in behalf of the current logged in user
        resp = self.requester.get(
            urljoin(
                self.base_url,
                '/api/certificates/v0/certificates/{username}/courses/{course_key}/'.format(
                    username=username,
                    course_key=course_id
                )
            )
        )

        resp.raise_for_status()

        return Certificate(resp.json())
Returns an Certificate object with the user certificates

        Args:
            username (str): an edx user's username
            course_id (str): an edX course id.

        Returns:
            Certificate: object representing the student certificate for a course