Check out example codes for "go get from map". It will help you in understanding the concepts better.

Code Example 1

// By default maps in Go behaves like a default dictionary in python
m := make(map[string]int)

m["Dio"] = 3
m["Jonathan"] = 1

Code Example 2

m := make(map[string]int)
m["numberOne"] = 1
m["numberTwo"] = 2

Code Example 3

var id string
var ok bool
if x, found := res["strID"]; found {
     if id, ok = x.(string); !ok {
        //do whatever you want to handle errors - this means this wasn't a string
     }
} else {
   //handle error - the map didn't contain this key
}

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