<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_comment_lookup_session_for_book(self, book_id, proxy):
 """Gets the ``OsidSession`` associated with the comment lookup service for the given book. arg: book_id (osid.id.Id):
 the ``Id`` of the ``Book`` arg: proxy (osid.proxy.Proxy):
 a proxy return: (osid.commenting.CommentLookupSession) - a ``CommentLookupSession`` raise: NotFound - no ``Book`` found by the given ``Id`` raise: NullArgument - ``book_id`` or ``proxy`` is ``null`` raise: OperationFailed - unable to complete request raise: Unimplemented - ``supports_comment_lookup()`` or ``supports_visible_federation()`` is ``false`` *compliance: optional -- This method must be implemented if ``supports_comment_lookup()`` and ``supports_visible_federation()`` are ``true``* """

        if not self.supports_comment_lookup():
            raise errors.Unimplemented()
        ##
        # Also include check to see if the catalog Id is found otherwise raise errors.NotFound
        ##
        # pylint: disable=no-member
        return sessions.CommentLookupSession(book_id, proxy, self._runtime)