Handle device closing a bit more sensibly

from serial import STOPBITS_ONE, STOPBITS_ONE_POINT_FIVE, STOPBITS_TWO

import io

import time

import warnings

import logging

import warnings

class ExtensibleSerialInstrument(object):

    """

            #be set to 1 byte for maximum responsiveness.

            assert self.test_communications(), "The instrument doesn't seem to be responding.  Did you specify the right port?"

    def close_serial_communications(self):

        """

        Close communication to the serial device. No exception handling.

        """

        with self.communications_lock:

            self._ser.close()

    def close(self):

        """Release the serial port"""

        """Cleanly close the device. Includes proper logging statements."""

        logging.debug("Closing serial connection")

        with self.communications_lock:

        try:

                self._ser.close()

            self.close_serial_communications()

        except Exception as e:

                logging.warning("The serial port didn't close cleanly:", e)

            logging.warning("The serial port didn't close cleanly: {}".format(e))

        logging.debug("Connection closed")

    def __del__(self):

        """Close the port when the object is deleted

        NB if the object is created in a with statement, this will cause

        the port to be closed at the end of the with block."""

        self.close()

        """Emergency close the device. Try to avoid having to use this."""

        if hasattr(self, '_ser') and self._ser.isOpen():

            print(

                "Closing an open serial communication has been triggered by garbage collection!\n"\

                "Please close this device more sensibly in future.")

            try:

                self.close_serial_communications()

            except Exception as e:

                print("The serial port didn't close cleanly: {}".format(e))

    def __enter__(self):

        return self

    def __exit__(self, type, value, traceback):

        """Close down the instrument.  This happens in __del__ though."""

        pass

        """Cleanly close down the instrument at end of a with block."""

        self.close()

    def write(self,query_string):

        """Write a string to the serial port"""

            else:

                return parsed_result

        except ValueError:

            logging.error("Parsing Error")

            logging.info("Matched Groups:", res.groups())

            logging.info("Parsing Functions:", parse_function)

            logging.info("Matched Groups: {}".format(res.groups()))

            logging.info("Parsing Functions {}:".format(parse_function))

            raise ValueError("Stage response to %s ('%s') couldn't be parsed by the supplied function" % (query_string, reply))

    def int_query(self, query_string, **kwargs):

        """Perform a query and return the result(s) as integer(s) (see parsedQuery)"""