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I want to decorate a class from a python module. How should I do it?

I am using a class from a module that I am importing. I want to extend this class: add some more attributes / methods. However, I want to keep all the functionality, including all possible constructors, of the source class.

Here is one way to do this:

class Extension(module.ModuleClass):
    def __init__(self, *args, **kwargs):
        newargument = kwargs.pop("myarg")
        super(Extension, self).__init__(*args, **kwargs)
        self.newargument = newargument

This seems to work, but has a minor syntax sugar issue and the following much more serious problems. ModuleClass overloads " +" operators, etc. Of course, Extension now benefits from this overload, but as a result of how they are implemented in ModuleClass, the result is of type ModuleClass, not Extension. That is, for Extensionobjects a, the bresult is a + bcorrectly defined, but it has a type ModuleClass, and not Extension. This is crucial.

Is there a better way to achieve expansion, for example, what am I looking for? Better in terms of saving types as a result of operations, is it easier to debug a line, easier to maintain, and more efficient?

, , ? .. , a ModuleClass, ( ) ModuleClass, , ..?

:

class Extension(object):
    def __init__(self, *args, **kwargs):
        self.myarg = kwargs.pop('timestamp')
        self.mclass = module.ModuleClass(*args, **kwargs)
    def __getattribute__(self, name):
        if (name == 'mclass'):
            return self.mclass
        elif (name == 'myarg'):
            return self.myarg
        else:
            return getattr(self.mclass, name)

, ( Extension Module ). ?

: "myarg = something", . ( , , "myarg = something" self.newargument. .

Extension(validValueForMyarg, validStuffToInitModuleClass)
Extension(validStuffToInitModuleClass, myarg = validValueForMyarg)

, ,

Extension(myarg = validValueForMyarg, validStuffToInitModuleClass)
+4
2

Extension.__init__ :

class Extension(module.ModuleClass):
    def __init__(self, myarg, *args, **kwargs):
        super(Extension, self).__init__(*args, **kwargs)
        self.newargument = myarg
+1

-

class Extension(module.ModuleClass):
    def __init__(self,*args, myarg=None, **kwargs):
        if myarg is None:
            raise ValueError('myarg is required')
        super(Extension, self).__init__(*args, **kwargs)
        self.newargument = myarg
+1

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