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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add(self, resource):
 """Add a resource change or an iterable collection of them. Allows multiple resource_change objects for the same resource (ie. URI) and preserves the order of addition. """

        if isinstance(resource, collections.Iterable):
            for r in resource:
                self.add_if_changed(r)
        else:
            self.add_if_changed(resource)