def METHOD_NAME(self):
    """
    Retrieves 1-based relative physical position in parent device.
    If the agent cannot determine the parent-relative position
    for some reason, or if the associated value of
    entPhysicalContainedIn is'0', then the value '-1' is returned
    Returns:
        integer: The 1-based relative physical position in parent device
        or -1 if cannot determine the position
    """
    return self.index + 1