code: def setup(pin, mode, pullup=None, initial=False):
      '''Setup pin with mode IN or OUT.
  
      Args:
          pin (int):
          mode (str): use either gpio.OUT or gpio.IN
          pullup (None): rpio compatibility. If anything but None, raises
              value Error
          pullup (bool, optional): Initial pin value. Default is False
      '''
      if pullup is not None:
          raise ValueError("sysfs does not support pullups")
  
      if mode not in (IN, OUT, LOW, HIGH):
          raise ValueError(mode)
  
      log.debug("Setup {0}: {1}".format(pin, mode))
      f = _open[pin].direction
      _write(f, mode)
      if mode == OUT:
          if initial:
              set(pin, 1)
          else:
              set(pin, 0f setup(pin, mode, pullup=None, initial=False):
      '''Setup pin with mode IN or OUT.
  
      Args:
          pin (int):
          mode (str): use either gpio.OUT or gpio.IN
          pullup (None): rpio compatibility. If anything but None, raises
              value Error
          pullup (bool, optional): Initial pin value. Default is False
      '''
      if pullup is not None:
          raise ValueError("sysfs does not support pullups")
  
      if mode not in (IN, OUT, LOW, HIGH):
          raise ValueError(mode)
  
      log.debug("Setup {0}: {1}".format(pin, mode))
      f = _open[pin].direction
      _write(f, mode)
      if mode == OUT:
          if initial:
              set(pin, 1)
          else:
              set(pin, 0)
docs: Setup pin with mode IN or OUT.
  
      Args:
          pin (int):
          mode (str): use either gpio.OUT or gpio.IN
          pullup (None): rpio compatibility. If anything but None, raises
              value Error
          pullup (bool, optional): Initial pin value. Default is False