def METHOD_NAME(instance_name: Optional[pulumi.Input[str]] = None,
                               managed_gateway_name: Optional[pulumi.Input[str]] = None,
                               resource_group_name: Optional[pulumi.Input[str]] = None,
                               opts: Optional[pulumi.InvokeOptions] = None) -> pulumi.Output[GetManagedGatewayResult]:
    """
    Retrieve the details of the gateway resource.
    Azure REST API version: 2023-07-07-preview.
    :param str instance_name: Name of the SCOM managed instance.
    :param str managed_gateway_name: The gateway resource name.
    :param str resource_group_name: The name of the resource group. The name is case insensitive.
    """
    ...