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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 remove_filter(self, server_id, filter_path):
 """ Remove an indication filter from a WBEM server, by deleting the indication filter instance in the WBEM server. The indication filter must be owned or permanent (i.e. not static). This method verifies that there are not currently any subscriptions on the specified indication filter, in order to handle server implementations that do not ensure that on the server side as required by :term:`DSP1054`. Parameters: server_id (:term:`string`):
 The server ID of the WBEM server, returned by :meth:`~pywbem.WBEMSubscriptionManager.add_server`. filter_path (:class:`~pywbem.CIMInstanceName`):
 Instance path of the indication filter instance in the WBEM server. Raises: Exceptions raised by :class:`~pywbem.WBEMConnection`. CIMError: CIM_ERR_FAILED, if there are referencing subscriptions. """


        # Validate server_id
        server = self._get_server(server_id)
        conn_id = server.conn.conn_id if server.conn is not None else None

        # Verify referencing subscriptions.
        ref_paths = server.conn.ReferenceNames(
            filter_path, ResultClass=SUBSCRIPTION_CLASSNAME)
        if ref_paths:
            # DSP1054 1.2 defines that this CIM error is raised by the server
            # in that case, so we simulate that behavior on the client side.
            raise CIMError(
                CIM_ERR_FAILED,
                "The indication filter is referenced by subscriptions.",
                conn_id=conn_id)

        server.conn.DeleteInstance(filter_path)

        inst_list = self._owned_filters[server_id]
        # We iterate backwards because we change the list
        for i in six.moves.range(len(inst_list) - 1, -1, -1):
            inst = inst_list[i]
            if inst.path == filter_path:
                del inst_list[i]