Traceback (most recent call last):
  File "pid_waveform.py", line 181, in <module>
    magnet_direction.set_value( 0 )
  File "pid_waveform.py", line 101, in set_value
    self._value_path.write_text( str( value ) )
  File "/usr/lib/python3.7/pathlib.py", line 1218, in write_text
    with self.open(mode='w', encoding=encoding, errors=errors) as f:
  File "/usr/lib/python3.7/pathlib.py", line 1186, in open
    opener=self._opener)
  File "/usr/lib/python3.7/pathlib.py", line 1039, in _opener
    return self._accessor.open(self, flags, mode)
FileNotFoundError: [Errno 2] No such file or directory: '/dev/gpio/magnet_dir/value'