def getSlope(p1, p2):
    return None if p2[0] - p1[0] == 0 else (p2[1] - p1[1]) / (p2[0] - p1[0])

'''
Task

Your challenge is to write a function named getSlope/get_slope/GetSlope that
 calculates the slope of the line through two points.

Input

Each point that the function takes in is an array 2 elements long.
 The first number is the x coordinate and the second number is the
 y coordinate. If the line through the two points is vertical or if
 the same point is given twice, the function should return null/None.
'''
