Knn Algorithm Basic Extension on python 2.7

knn.py

import math

def distance(class_of_cluster,x1,x2,y1,y2):
	y_square = math.pow((y2-y1),2)
	x_square = math.pow((x2-x1),2)

	return class_of_cluster,math.sqrt(x_square+y_square)


def knn(data_set,target_data,neighbors_count):
	distances = []
	for cl_data in data_set: 
		distances.append(distance(cl_data[0],example_data[0][0],cl_data[1],example_data[0][1],cl_data[2]))

	
	return distances[0][0],distances[:neighbors_count]


data_arr = [('A',1,2),('A',2,3),('A',4,3),('B',5,6),('B',6,7),('B',7,8),('B',8,9)]

example_data = [(1,3)]



print knn(data_arr,example_data,3)