def add(self, elem, replace=False):
        """Add a requirement.

        :param elem: a string or :class:`Requirement` instance.
        :param replace: if `True`, packages in the set with the same name will
            be removed first.
        """
        if isinstance(elem, text_type):
            elem = Requirement.coerce(elem)
        if replace and elem in self:
            self.remove(elem)
        super(Requirements, self).add(elem)
def gpio_init(pin, output):
  try:
    with open(f"/sys/class/gpio/gpio{pin}/direction", 'wb') as f:
      f.write(b"out" if output else b"in")
  except Exception as e:
    print(f"Failed to set gpio {pin} direction: {e}")