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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 _get_item_class(self, url):
 """ Return the model class matching a URL """

        if '/layers/' in url:
            return Layer
        elif '/tables/' in url:
            return Table
        elif '/sets/' in url:
            return Set
        # elif '/documents/' in url:
        #     return Document
        else:
            raise NotImplementedError("No support for catalog results of type %s" % url)