Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Gains 300 ATK for each Continuous Spell in your Spell & Trap Zone.
--龍脈に棲む者
--Dweller in the Depths
local s,id=GetID()
function s.initial_effect(c)
	--destroy
	local e1=Effect.CreateEffect(c)
	e1:SetProperty(EFFECT_FLAG_SINGLE_RANGE)
	e1:SetType(EFFECT_TYPE_SINGLE)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCode(EFFECT_UPDATE_ATTACK)
	e1:SetValue(s.atkval)
	c:RegisterEffect(e1)
end
function s.cfilter(c)
	return c:IsFaceup() and c:IsContinuousSpell() and c:GetSequence()~=5
end
function s.atkval(e,c)
	return Duel.GetMatchingGroupCount(s.cfilter,c:GetControler(),LOCATION_SZONE,0,nil)*300
end