def METHOD_NAME(self, mock_post):
    """
    Test for an invalid course key
    """
    missing_course_key = CourseKey.from_string('course-v1:FakeOrganization+CN999+CR-FALL99')
    assert ccxconapi.course_info_to_ccxcon(missing_course_key) is None
    assert mock_post.call_count == 0