How to Marshal (using protojson package) array of proto to json in Golang?

How to achieve the following with protojson package in Golang?

Protobuf:

type ProtoResp struct {
  state         protoimpl.MessageState
  sizeCache     protoimpl.SizeCache
  unknownFields protoimpl.UnknownFields

  Xesp isActionResponse_Xesp `protobuf_oneof:"xesp"`
  TimeTakena string `protobuf:"bytes,9,opt,name=time_takena,json=timeTakena,proto3" json:"time_takena,omitempty"`
}

So, I need to marshal the array of proto into a json. For example,

var protoResps []ProtoResp

How do I marshal this protoResps?

Currently, protojson.Marshal function can marshal ProtoResp but can't marshal []ProtoResp as its slice of proto.

I also need to unmarshal this later back into []ProtoResp

Thanks in advance.