所以，在我的Python代码中有这样的东西：
company = None
country = None
person = Person.find（id = 12345）
如果人不是None：＃found
company = Company.find（person.companyId）
如果公司不是None：
country = Country。 find（company.countryId）
return（person，company，country）
阅读了Haskell monads（特别是 Maybe ）的教程后，我想知道是否可以用另一种方式编写它。
解决方案 company = country = None
try：
person = Person.find（id = 12345）
company = Company.find（person.companyId）
country = Country.find（company.countryId）
，但AttributeError：
pass＃`person`或`company`可能是None
Trying to find a way to clean up some of my code.
So, I have something like this in my Python code:
company = None
country = None
person = Person.find(id=12345)
if person is not None: # found
company = Company.find(person.companyId)
if company is not None:
country = Country.find(company.countryId)
return (person, company, country)
Having read a tutorial on Haskell's monads (in particular Maybe), I was wondering if it's possible to write it in another way.
company = country = None
try:
person = Person.find(id=12345)
company = Company.find(person.companyId)
country = Country.find(company.countryId)
except AttributeError:
pass # `person` or `company` might be None
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