class Shape:
    def __init__(self, x=0, y=0, z=0):
        self.x = x
        self.y = y
        self.z = z

    def move(self, x_amount, y_amount):
        self.x += x_amount
        self.y += y_amount

    def __str__(self):
        return "Shape at ({}, {})".format(self.x, self.y)
