find, read and parse configuraton.

def _get_config(config_file):
    '''find, read and parse configuraton.'''
    parser = ConfigParser.SafeConfigParser()
    if os.path.lexists(config_file):
        try:
            log.info('Reading config: %s', config_file)
            inp = open(config_file)
            parser.readfp(inp)
            return parser
        except (IOError, ConfigParser.ParsingError), err:
            raise ConfigError("Failed to read configuration %s\n%s" % (config_file, err))
    return None