Do you know anything about explosive devices?
Can you tell by looking that it is 'harmless' because it has a 'happy face' on the outside?
I say again, this is no time to play such games.
Funny, NOT!
"If you found a "package" in your place, how would you determine if it was harmless or not?"
You are talking about ones own home.
There is a big difference between coming home and finding something in your own house, then say, walking down the street and seeing a cylinder with a blinking light on it.
Oh, I don't know. Perhaps look at it and use the brain that God gave me. But that's just me.