为什么教师名称输出不对

# 描述文件example.py
class Student(object):
   def __init__(self, s_number, name, course = None):
       """
       描述学生的学号、姓名、已选课程
       :param s_number: 学生学号
       :param name: 学生姓名
       :param course: 已选课程(默认值为空列表)
       """
       self.s_number = s_number
       self.name = name
       self.course = course

   def course_detail(self):
       return self.course

   def add_course(self,cour_info):
       self.course = cour_info

   def __str__(self):
       return 'name:{0},s_number:{1}'.format(self.name, self.s_number)


class Teacher(object):
   def __init__(self, t_number, t_name, phone_number):
       """
       描述教师编号、教师姓名、手机号码
       :param t_number:教师编号
       :param t_name:教师姓名
       :param phone_number:手机号码
       """
       self.t_number = t_number
       self.t_name = t_name
       self.phone_number = phone_number

   def __str__(self):
       return self.t_number, self.t_name


class Course(object):
   def __init__(self, course_number, course_name, teacher = None):
       """
       描述课程编号、课程名称、授课教师
       :param course_number:课程编号
       :param course_name:课程名称
       :param teacher:授课教师
       """
       self.course_number = course_number
       self.course_name = course_name
       self.teacher = teacher

   def binding(self, teacher):
       if not teacher:
           return
       self.teacher = teacher
       course_dict = {'课程名称': self.course_name, '教师名称': self.teacher}
       return course_dict

# 启动文件file_exe.py

from example import Course, Teacher, Student


def introduction(str):
   print('{0}{1}{2}'.format('**********', str, '**********'))


def prepare_course():
   course_dit = {"01": "网络爬虫", "02": "数据分析", "03": "人工智能", "04": "机器学习",
                 "05": "云计算", "06": "大数据", "07": "图像识别", "08": "Web开发"}
   course_list = []
   for course_number, course_name in course_dit.items():
       course = Course(course_number, course_name)
       course_list.append(course)
   return course_list


def create_teacher():
   teacher_info_list = [["T1", "张亮", "13301122001"], ["T2", "王朋", "13301122002"],
                   ["T3", "李旭", "13301122003"], ["T4", "黄国发", "13301122004"],
                   ["T5", "周勤", "13301122005"], ["T6", "谢富顺", "13301122006"],
                   ["T7", "贾教师", "13301122007"], ["T8", "杨教师", "13301122008"]
                   ]
   teacher_list = []
   for i in teacher_info_list:
       teacher_info = Teacher(i[0], i[1], i[2])
       teacher_list.append(teacher_info)
   return teacher_list


def course_to_teacher():
   course_teacher_list = []
   is_course = prepare_course()
   is_teacher = create_teacher()
   for i in range(len(is_course)):
       bind = is_course[i].binding(is_teacher[-(i - 1)])
       course_teacher_list.append(bind)
   return course_teacher_list


def create_student():
   is_student = ["小亮", "小明", "李红", "小丽", "乔治", "小彤", "小凯", "慕慕"]
   student_number = range(1000, 1008)
   student_list = []
   for w in range(len(is_student)):
       student_info = Student(student_number[w], is_student[-(w + 1)])
       student_list.append(student_info)
   return student_list


if __name__ == "__main__":
   student_info_list = create_student()
   choose_list = course_to_teacher()
   introduction("慕课学院(1)班学生信息")
   for student in student_info_list:
       print(student)
   introduction("慕课学院(1)班选课信息")
   for i in range(len(choose_list)):
       student_info_list[i].add_course(choose_list[i])
   for i in student_info_list:
       print("name: {0}, Selected: {1}".format(i.name, i.course_detail()))