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Start your free trialYu-Che Hung
Courses Plus Student 10,607 Pointswhy this will return false?
why this will return false?
2 Answers
annecalija
9,031 PointsHi Yu-che,
As far as I understand the question, it only evaluates if the line
Orange().squeeze()
will return True.
That means, if it will return True, we choose to answer "True" from the quiz options.
And if the line does not return True, "False" being the correct quiz answer, that does not necessarily mean, that the line already returns False, opposing your main question "Why this will return false"
In fact, it does not return False. It returns a NameError (which is a valid condition to select "False" as the answer):
>>> from fruits import Orange
>>> Orange().squeeze()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\fruits.py", line 8, in squeeze
return has_pulp
NameError: name 'has_pulp' is not defined
# fruits.py
class Fruit:
has_pulp = False
class Orange(Fruit):
has_pulp = True
def squeeze(self):
return has_pulp
This is because the the squeeze() method which is called by the instance does not know the class variable has_pulp. It only knows the attribute of the instance that called it which is why self.pulp is valid.
Hope this helps.
annecalija
9,031 PointsHi,
From the question:
class Orange(Fruit): has_pulp = True def squeeze(self): return has_pulpOrange().squeeze() will return True.
The mistake is that in function,
def squeeze(self):
the value returned was
return has_pulp
instead of
return self.has_pulp
Yu-Che Hung
Courses Plus Student 10,607 PointsAnne thank you But why? why I have to add "return self.has_pulp" so that it will return True?
Yu-Che Hung
Courses Plus Student 10,607 PointsYu-Che Hung
Courses Plus Student 10,607 Pointsthank you ANNE ! You really helped me a lot!