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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 find(cls, session, resource_id, include=None):
 """Retrieve a single resource. This should only be called from sub-classes. Args: session(Session):
 The session to find the resource in resource_id: The ``id`` for the resource to look up Keyword Args: include: Resource classes to include Returns: Resource: An instance of a resource, or throws a :class:`NotFoundError` if the resource can not be found. """

        url = session._build_url(cls._resource_path(), resource_id)
        params = build_request_include(include, None)
        process = cls._mk_one(session, include=include)
        return session.get(url, CB.json(200, process), params=params)