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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 get_exported_interfaces(svc_ref, overriding_props=None):
 # type: (ServiceReference, Optional[Dict[str, Any]]) -> Optional[List[str]] """ Looks for the interfaces exported by a service :param svc_ref: Service reference :param overriding_props: Properties overriding service ones :return: The list of exported interfaces """

    # first check overriding_props for service.exported.interfaces
    exported_intfs = get_prop_value(
        SERVICE_EXPORTED_INTERFACES, overriding_props
    )
    # then check svc_ref property
    if not exported_intfs:
        exported_intfs = svc_ref.get_property(SERVICE_EXPORTED_INTERFACES)

    if not exported_intfs:
        return None

    return get_matching_interfaces(
        svc_ref.get_property(constants.OBJECTCLASS), exported_intfs
    )