Please list the full names of all the students who took the course Machine Learning Theory.
full name refers to f_name and l_name;
SELECT T1.f_name, T1.l_name FROM student AS T1 INNER JOIN registration AS T2 ON T1.student_id = T2.student_id INNER JOIN course AS T3 ON T2.course_id = T3.course_id WHERE T3.name = 'Machine Learning Theory'