code: def _open(self, file_path=None):
  		
  		if file_path is None:
  			file_path = self.file_path
  
  		if not os.path.exists(file_path):
  			raise ValueError('Could not find file: {}'.format(file_path))
  
  		try:
  			f = open(file_path, encoding='utf-8', newline='')
  		except OSError as err:
  			self.log.error(str(err))
  			raise ValueError('Could not open file: {}'.format(file_path))
  
  		return f
docs: Opens the file specified by the given path. Raises ValueError if there
  		is a problem with opening or reading the file.