def loads(self, requirements_text):
        lines = re.findall(Requirement.spec_regex,
                           requirements_text,
                           re.MULTILINE)
        for line in lines:
            self.add(Requirement(line[0], "".join(line[1:])))
def __init__(self, p1, p2):
        self.p1 = p1
        self.p2 = p2
        self.length = math.sqrt(math.pow((self.p2.x - self.p1.x), 2) + math.pow((self.p2.y - self.p1.y), 2))