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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 PostRegistration(method):
 # pylint: disable=C0103 """ The service post-registration callback decorator is called after a service of the component has been registered to the framework. The decorated method must accept the :class:`~pelix.framework.ServiceReference` of the registered service as argument:: @PostRegistration def callback_method(self, service_reference):
 ''' service_reference: The ServiceReference of the provided service ''' :param method: The decorated method :raise TypeError: The decorated element is not a valid function """

    if not isinstance(method, types.FunctionType):
        raise TypeError("@PostRegistration can only be applied on functions")

    # Tests the number of parameters
    validate_method_arity(method, "service_reference")
    _append_object_entry(
        method,
        constants.IPOPO_METHOD_CALLBACKS,
        constants.IPOPO_CALLBACK_POST_REGISTRATION,
    )
    return method