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 draw(self, context):
        from rna_keymap_ui import draw_keymaps

        layout = self.layout

        #import time

        #start = time.time()

        userpref = context.user_preferences

        inputs = userpref.inputs

        split = layout.split(percentage=0.25)

        # Input settings
        self.draw_input_prefs(inputs, split)

        # Keymap Settings
        draw_keymaps(context, split)

        #print("runtime", time.time() - start)