Getting error "Variable 'CustomKeywords' is not defined for test case"

Getting error “Variable ‘CustomKeywords’ is not defined for test case” when calling one custom keyword of one package into another custom keyword in another package. Called CustomKeywords is underlined. In below example on mobile, I want call scroll customkeyword into keyword abc.

@Keyword

def abc(){

for(int i=1; i<=20; i++){

<>

if(b==true){

<>

}else{

<>

CustomKeywords.‘general_utilities.Scroll.scrollbyTouchHorizontal’()

}

}

}

Please help me out what is mising and how I can solve this issue?

Instead of CustomKeywords.‘general_utilities.Scroll.scrollbyTouchHorizontal’()
use (new general_utilities.Scroll()).scrollbyTouchHorizontal()