python - Is it more pythonic to manipulate object I/O with @property vs override __getitem__? -

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given dictionary of data (could come database entry), more correct way wrap dictionary's data in encapsulating class has control on data can set , returned as?

specifically, 2 ways have in mind to:

  1. override dict inherited class' __getitem__ , __setitem__ methods
  2. within standard object inherited class, add @property decorator each data entry needs controlled.

for example:

class smartcontainer(dict):      ## format/check items returned     def __getitem__(self,key):         if key == "birthday":             return "happy birthday!{bdate}".format(bdate=self.get('birthday'))         if key not in self.keys():             return 0      def __init__(self,basedict):         super(smartcontainer,self).__init__(basedict)  class smartcontainer2(object):     @property     def birthday(self):         return "happy birthday! {bdate}".format(bdate=self._birthday)     @birthday.setter     def birthday(self,value):         self._birthday = value      def __init__(self, basedict):         [self.__setattr__(k,v) k,v in basedict.iteritems()]

in purely arbitrary example, have 2 classes implement each architecture. 

smartcontainer=smartcontainer({"pi":3.14, "birthday":"01/01/2016"}) smartcontainer['birthday']  >>>'happy birthday! 01/01/2016'  smartcontainer2=smartcontainer2({"pi":3.14, "birthday":"01/01/2016"}) smartcontainer2.birthday  >>>'happy birthday! 01/01/2016'

both methods work, , seems me @property decorator more used such actions. dynamic nature of smartcontainer class' access abilities seem more straightforward me. aka smartcontainer[dynamic_key] vs smartcontainer2.__getattr__(dynamic_key).

i wondering if there reason use 1 method on other, , potential pitfalls exist?


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