def load(self, requirements_file=None):
        """Load or reload requirements from a requirements.txt file.

        :param requirements_file: if not given, the filename used from
            initialization will be read again.
        """
        if requirements_file is None:
            requirements_file = self.filename
            if requirements_file is None:
                raise ValueError("no filename provided")
        elif isinstance(requirements_file, text_type):
            requirements_file = Path(requirements_file)
        self.clear()
        with requirements_file.open() as f:
            self.loads(f.read())

        if isinstance(requirements_file, (text_type, Path)):
            self.filename = requirements_file
def drawMe(self, g):
        self.g = g
        r = 5
        # 繪出三個頂點
        self.p1.drawMe(self.g,r)
        self.p2.drawMe(self.g,r)
        self.p3.drawMe(self.g,r)
        line1 = Line(self.p1,self.p2)
        line2 = Line(self.p1,self.p3)
        line3 = Line(self.p2,self.p3)
        # 繪出三邊線
        line1.drawMe(self.g)
        line2.drawMe(self.g)
        line3.drawMe(self.g)