Iterating through a golang map

I have a map of type: map[string]interface{}

And finally, I get to create something like (after deserializing from a yml file using goyaml)

mymap = map[foo:map[first: 1] boo: map[second: 2]]

How can I iterate through this map? I tried the following:

for k, v := range mymap{
...
}

But I get an error:

cannot range over mymap
typechecking loop involving for loop

Please help.

For example,

package main

import "fmt"

func main() {
	type Map1 map[string]interface{}
	type Map2 map[string]int
	m := Map1{"foo": Map2{"first": 1}, "boo": Map2{"second": 2}}
	//m = map[foo:map[first: 1] boo: map[second: 2]]
	fmt.Println("m:", m)
	for k, v := range m {
		fmt.Println("k:", k, "v:", v)
	}
}

Output:

m: map[boo:map[second:2] foo:map[first:1]]
k: boo v: map[second:2]
k: foo v: map[first:1]

You could just write it out in multiline like this,

$ cat dict.go
package main

import "fmt"

func main() {
        items := map[string]interface{}{
                "foo": map[string]int{
                        "strength": 10,
                        "age": 2000,
                },
                "bar": map[string]int{
                        "strength": 20,
                        "age": 1000,
                },
        }
        for key, value := range items {
                fmt.Println("[", key, "] has items:")
                for k,v := range value.(map[string]int) {
                        fmt.Println("\t-->", k, ":", v)
                }

        }
}

And the output:

$ go run dict.go
[ foo ] has items:
        --> strength : 10
        --> age : 2000
[ bar ] has items:
        --> strength : 20
        --> age : 1000

You can make it by one line:

mymap := map[string]interface{}{"foo": map[string]interface{}{"first": 1}, "boo": map[string]interface{}{"second": 2}}
for k, v := range mymap {
	fmt.Println("k:", k, "v:", v)
}

Output is:

k: foo v: map[first:1]
k: boo v: map[second:2]