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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def read(path):
 """ Returns the process id from the given file if it exists, or None otherwise. Raises an exception for all other types of OSError while trying to access the file. :type path: str :param path: The name of the pidfile. :rtype: int or None :return: The PID, or none if the file was not found. """

    # Try to read the pid from the pidfile.
    logging.info("Checking pidfile '%s'", path)
    try:
        return int(open(path).read())
    except IOError as xxx_todo_changeme:
        (code, text) = xxx_todo_changeme.args
        if code == errno.ENOENT:  # no such file or directory
            return None
        raise