function myfilter takes nothing returns boolean
   return IsPlayerEnemy(GetOwningPlayer(GetTriggerUnit()), GetOwningPlayer(GetFilterUnit())) and GetWidgetLife(GetFilterUnit()) > 0.405 
endfunction

function myfunc2 takes nothing returns  nothing
...
   local boolexpr b = Condition(function myfilter)
   local group g = CreateGroup()
   call GroupEnumUnitsInRange(g,GetUnitX(caster), GetUnitY(caster), range, b)
...
endfunction

function myfunc1 takes nothing returns nothing
...
   call TimerStart(tr, 4.0, false, function myfunct2)
...
endfunction

Condition(function myfilter)

Filter(function myfilter)

// globals
        unit ForFilter1


bool EnemiesFilter(){
return (IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(ForFilter1)) and GetHp(GetFilterUnit()) > 0.045)
}

.....
ForFilter1 = caster
GroupEnumUnitsInRange(g,GetUnitX(caster), GetUnitY(caster), range, Filter(function myfilter))

// globals
        unit ForFilter1


bool EnemiesFilter(){
return (IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(ForFilter1)) and GetHp(GetFilterUnit()) > 0.045)
}

.....
ForFilter1 = caster
GroupEnumUnitsInRange(g,GetUnitX(caster), GetUnitY(caster), range, Filter(function myfilter))

function EnemiesFilter takes nothing returns boolean
return (IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(ForFilter1)) and GetUnitState(GetFilterUnit(), UNIT_STATE_LIFE) > 0.045)
endfunction

...
set ForFilter1 = caster
call GroupEnumUnitsInRange(g, GetUnitX(caster), GetUnitY(caster), range, Filter(function EnemiesFilter))