list only direct followers in csvreport

[vijay]

I have the following tasks

task a "A" { effort 1w  allocate jvs}
task b "B" {  depends !a allocate jvs
task  b1 "B1" { effort 1w  }
task  b2 "B2" { effort 1w  }}
task c "C" {  depends !a allocate jvs}

I want to postprocess the csvreport and get a list of declared followers (e.g. b,c are declared followers for a b1,b2 are inferred followers)

I have declared columns ..., followers  to achieve this.

I get the following output.

"B (feyzus.b) ]->[ 2024-04-08, B1 (feyzus.b.b1) ]->[ 2024-04-08, B2 (feyzus.b.b2) ]->[ 2024-04-15, C (feyzus.c) ]->[ 2024-04-05"

What should I do to get an output without B1 and B2?