python - 打印和格式化实例

Question

我试图在此处为此类定义一个str 方法，以便在打印 Student 类的实例时，它会打印以下格式的内容:我的名字是 ___。我上大学已经 __ 年了，我编写了 __ 程序。在正确的措辞下方是打印，但正确的值未打印。任何帮助将不胜感激。

class Student():
def __init__(self, name, years_at_umich=1):
    self.name = name
    self.years_UM = years_at_umich
    self.bonus_points = random.randrange(1000)
    self.programs_written = 0
def __str__(self):
    return "My name is %s. I've been in college for %d years and I've written %d programs" \
        %(self.name, self.years_UM, self.programs_written)
def shout(self, phrase_to_shout):
    print phrase_to_shout  

def year_at_umich(self):
    return self.years_UM

def write_programs(self, progs=1):
    self.programs_written += progs
    return self.programs_written

---

*** 测试不同的值，目前它只通过了学生 4 的最后一次测试********

class Student_test(unittest.TestCase):
    def test_student1(self):
        student1 = Student("Lyra")
        self.assertEqual(student1.__str__(),"My name is Lyra. I've been at UMich for 1 years and I've written 0 programs.")
    def test_student2(self):
        student2 = Student("Aisha")
        student2.write_programs()
        self.assertEqual(student2.__str__(),"My name is Aisha. I've been at UMich for 1 years and I've written 1 programs.")
    def test_student3(self):
        student3 = Student("Ali",3)
        student3.write_programs(4)
        self.assertEqual(student3.__str__(),"My name is Ali. I've been at UMich for 3 years and I've written 4 programs.")
    def test_student4(self):
        student4 = Student("Aja")
    student4.write_programs(12)
    self.assertEqual(student4.programs_written, 12)
    student4.write_programs()
    self.assertEqual(student4.programs_written,13)

Answer 1

class Student():
  def shout(num, word):
    if num == 1:
      phrase = "My name is %s" % word
    elif num == 2:
      phrase = "I love %s" % word
    elif num == 3:
      phrase = "My favorite food is %s" % word
    return phrase

  def years(num):
    phrase = "I've been at umich for %s years" % num
    return phrase

  def programs(num):
    phrase = "I've written %s programs" % num
    return phrase

Student.shout(1, 'Mud')
'My name is Mud'