go ensure implementation

package main

import (
    "fmt"
    "reflect"
)

func main() {
    // Create a map with string keys and int values
    myMap := map[string]int{
        "apple":  23,
        "banana": 17,
        "orange": 9,
    }

    // Print the initial map
    fmt.Println("Initial Map:", myMap)

    // Ensure a key "grapes" exists in the map with a value of 13
    ensureKeyExists(myMap, "grapes", 13)

    // Print the modified map
    fmt.Println("Modified Map:", myMap)
}

// Function to ensure a key exists in a map with a specific value
func ensureKeyExists(m map[string]int, key string, value int) {
    // Check if the key exists in the map
    if _, ok := m[key]; !ok {
        // If the key doesn't exist, add it with the specified value
        m[key] = value
        fmt.Printf("Key '%s' added with value '%d'\n", key, value)
    } else {
        // If the key already exists, print a message indicating its presence
        fmt.Printf("Key '%s' already exists with value '%d'\n", key, m[key])
    }
}

Explanation:

1. The code starts with a main package declaration and imports necessary packages: "fmt" for formatting and "reflect" for reflection capabilities.

2. Inside the main() function:

3. A map myMap is initialized with string keys and integer values.

4. The initial map content is printed using fmt.Println.

5. ensureKeyExists() is a custom function that ensures a specified key exists in the map with a specific value:

6. It takes a map (m), a key (key), and a value (value) as arguments.
7. It checks if the key exists in the map using the existence check syntax: if _, ok := m[key]; !ok.
8. If the key does not exist (!ok), it adds the key-value pair to the map and prints a message confirming the addition.

9. If the key already exists, it prints a message indicating its presence.

10. In main(), the ensureKeyExists() function is called to ensure the key "grapes" exists in myMap with a value of 13.

11. Finally, after the function call, the modified map content is printed using fmt.Println.