A cool thing about a Go map or a dictionary, is that if a key is not initialized, then it returns the default value.

Here's an example:

intmap := make(map[int]bool)

Suppose now you add an entry into intmap with:

intmap[1] = true

And you retrieve a non-existent key: 

boolval := intmap[2]

boolval will then contain a value of false, the default value for a boolean in Go.