$1$ K$-$Nearest Neighbors $($KNN$)$ Classifier

$1\mathrm{.}1$ Create and Train K$-$NN Model

You are tasked with creating and training a K$-$Nearest Neighbors $($KNN$)$ model. Your goal is to understand how to implement a KNN classifier and train your model on a given dataset.

Objective:

Create and train a KNN model using the input training set.

Return the trained model.

Requirements:

The function should be named create$\_$and$\_$train$\_$knn$\_$model.

Parameters:

X$\_$train : A $2$D array of the training features.

y$\_$train: A $1$D array of the training labels.

$k$ : An integer representing the number of neighbors to consider. The default value should be $1.$

Return:

The function should return the trained KNN model, which is trained onn the input training data and with the input value of $k.$