How to Parser the "Nested" Json

hi everyone , the json like:

"vecMap":
{
		"A":
		[	
			{
				"id": "a",
				"alpha": 1
			},
			{
				"id": "b",
				"alpha": 2
			}
		],
		"B":
		[	
			{
				"id": "c",
				"alpha": 3
			},
			{
				"id": "d",
				"alpha": 4
			}
		]
}

i need to make a custom Property like:

USTRUCT()
struct FData
{
	GENERATED_USTRUCT_BODY()

		FString Id;
	UPROPERTY()
		float Alpha;
};

UPROPERTY()
TMap<FString, TArray<FData>> vecMap;//break out ERROR at here

but when i building the error is break out : “Nested containers are not supported.”

so Do you have any suggestions or methods to Parsering the nested json?

i fix it

to see → how to support nested JSON Struct at UE4 click me