text: """
  UART based message handler for CircuitPython logging.
  
  Adafruit invests time and resources providing this open source code.
  Please support Adafruit and open source hardware by purchasing
  products from Adafruit!
  
  Written by Dave Astels for Adafruit Industries
  Copyright (c) 2018 Adafruit Industries
  Licensed under the MIT license.
  
  All text above must be included in any redistribution.
  """
  
  
  # Example:
  #
  # import board
  # import busio
  # from uart_handler import UartHandler
  # import adafruit_logging as logging
  #
  # uart = busio.UART(board.TX, board.RX, baudrate=115200)
  # logger = logging.getLogger('uart')
  # logger.addHandler(UartHandler(uart))
  # logger.level = logging.INFO
  # logger.info('testing')
  
  from adafruit_logging import LoggingHandler
  
  class UartHandler(LoggingHandler):
      """Send logging output to a serial port."""
  
      def __init__(self, uart):
          """Create an instance.
  
          :param uart: the busio.UART instance to which to write messages
  
          """
          self._uart = uart
  
      def format(self, level, msg):
          """Generate a string to log.
  
          :param level: The level at which to log
          :param msg: The core message
  
          """
          return super().format(level, msg) + '\r\n'
  
      def emit(self, level, msg):
          """Generate the message and write it to the UART.
  
          :param level: The level at which to log
          :param msg: The core message
  
          """
          self._uart.write(bytes(self.format(level, msg), 'utf-8'))
  