Point objects have x and y attributes (X and Y in C#) attributes. Write a function calculating distance between Point a and Point b. Tests round answers to 6 decimal places.

import math

class Point:
    def __init__(self, x, y):
        self.x = x
        self.y = y

def distance(a, b):
    return math.sqrt((a.x - b.x)**2 + (a.y - b.y)**2)