def UpdateStatus(self, is_complete):
    '''Mock method to update the transfer status.

    If is_complete is False, this marks the transfer is active; otherwise it
    marks the transfer as complete. It is an error to call this method after
    calling it with is_complete as True.

    In both cases, it updates the number of bytes transferred to be the current
    size of the transfer file (whose filename was emitted in the
    TransferCreated signal).
    '''
    status = 'complete' if is_complete else 'active'
    transferred = os.path.getsize(self.props[TRANSFER_IFACE]['Filename'])

    self.props[TRANSFER_IFACE]['Status'] = status
    self.props[TRANSFER_IFACE]['Transferred'] = dbus.UInt64(transferred, variant_level=1)

    self.EmitSignal(dbus.PROPERTIES_IFACE, 'PropertiesChanged', 'sa{sv}as', [
        TRANSFER_IFACE,
        {
            'Status': dbus.String(status, variant_level=1),
            'Transferred': dbus.UInt64(transferred, variant_level=1),
        },
        [],
    ])
Mock method to update the transfer status.

    If is_complete is False, this marks the transfer is active; otherwise it
    marks the transfer as complete. It is an error to call this method after
    calling it with is_complete as True.

    In both cases, it updates the number of bytes transferred to be the current
    size of the transfer file (whose filename was emitted in the
    TransferCreated signal).