old_contents: class Sensor:
      def __init__(self, read_stream):
          """
          Create a new sensor. 
          
          :param read_stream: A stream object (serial, file, etc.)
          """
  
          self.read_stream = read_stream
  
      def read_data(self) -> str:
          """
          Reads data from the stream until a newline character is encountered. 
          """
  
          result = self.read_stream.readline()
          return result
  
      def close(self):
          """
          Closes the underlying stream object. This sensor will no longer be able to be read from.
          """
  
          stream.close()
  
new_contents: class Sensor:
      def __init__(self, read_stream):
          """
          Create a new sensor. 
          
          :param read_stream: A stream object (serial, file, etc.)
          """
  
          self.read_stream = read_stream
  
      def read_data(self) -> str:
          """
          Reads data from the stream until a newline character is encountered. 
          """
  
          result = self.read_stream.readline()
          return result
  
      def close(self):
          """
          Closes the underlying stream object. This sensor will no longer be able to be read from.
          """
  
          self.read_stream.close()
  
subject: Read stream data