Simple Entity can't be used with Grav Gun?

For some reason this Entity won’t do anything when right clicked with a Grav Gun:

[LUA]
AddCSLuaFile(“cl_init.lua”)
AddCSLuaFile(“shared.lua”)

include(“shared.lua”)

function ENT:Initialize()
self.Entity:SetModel(“models/weapons/w_bugbait.mdl”)
self.Entity:SetNWBool(“Weed”, true)
self.Entity:PhysicsInit(SOLID_VPHYSICS)
self.Entity:SetMoveType(MOVETYPE_VPHYSICS)
self.Entity:SetSolid(SOLID_VPHYSICS)
self.Entity:SetUseType(SIMPLE_USE)
self.Entity:SetColor(0, 255, 0, 255)
local phys = self.Entity:GetPhysicsObject()
if phys and phys:IsValid() then phys:Wake() end
self.sparking = false
self.damage = 100
local ply = self.Entity:GetNWEntity(“owning_ent”)
end

function ENT:OnTakeDamage(dmg)
self.damage = self.damage - dmg:GetDamage()
if (self.damage <= 0) then
self.Entity:Remove()
end
end

function ENT:Use()
end

function ENT:OnRemove()
timer.Destroy(self.Entity:EntIndex())
local ply = self.Entity:GetNWEntity(“owning_ent”)
if not ValidEntity(ply) then return end
end
[/LUA]

Put this under you check for the PhysicsObject:
phys:SetMass(20)