How to use the fusesoc.utils.pr_warn function in fusesoc

xdg_data_home = os.environ.get('XDG_DATA_HOME') or \
                    os.path.join(os.path.expanduser('~'),
                                 '.local', 'share', 'fusesoc')
    _repo_paths = []
    for repo in REPOS:
        default_dir = os.path.join(xdg_data_home, repo[0])
        prompt = 'Directory to use for {} ({}) [{}] : '
        if args.y:
            cores_root = None
        else:
            cores_root = input(prompt.format(repo[0], repo[2], default_dir))
        if not cores_root:
            cores_root = default_dir
        if os.path.exists(cores_root):
            pr_warn("'{}' already exists".format(cores_root))
            #TODO: Prompt for overwrite
        else:
            _repo_paths.append(cores_root)
            pr_info("Initializing {}".format(repo[0]))
            git_args = ['clone', repo[1], cores_root]
            try:
                Launcher('git', git_args).run()
            except RuntimeError as e:
                pr_err("Init failed: " + str(e))
                exit(1)

    xdg_config_home = os.environ.get('XDG_CONFIG_HOME') or \
                      os.path.join(os.path.expanduser('~'), '.config')
    config_file = os.path.join(xdg_config_home, 'fusesoc', 'fusesoc.conf')

def load_section(config, section_name, file_name=''):
    tmp = section_name.split(' ')
    _type = tmp[0]
    if len(tmp) == 2:
        _name = tmp[1]
    else:
        _name = None
    cls = SECTION_MAP.get(_type)
    if cls is None:
        #Note: The following sections are not in section.py yet
        if not section_name in ['plusargs', 'simulator', 'provider']:
            pr_warn("Unknown section '{}' in '{}'".format(section_name, file_name))
        return None

    items = config.get_section(section_name)
    section = cls(items)
    if section.warnings:
        for warning in section.warnings:
            pr_warn('Warning: %s in %s' % (warning, file_name))
    if _name:
        return (section, _name)
    else:
        return section

config = Config()

    # Get the environment variable for further cores
    env_cores_root = []
    if os.getenv("FUSESOC_CORES"):
        env_cores_root = os.getenv("FUSESOC_CORES").split(":")
    env_cores_root.reverse()

    for cores_root in [config.cores_root,
                       config.systems_root,
                       env_cores_root,
                       args.cores_root]:
        try:
            cm.add_cores_root(cores_root)
        except (RuntimeError, IOError) as e:
            pr_warn("Failed to register cores root '{}'".format(str(e)))
    # Process global options
    if vars(args)['32']:
        config.archbits = 32
        logger.debug("Forcing 32-bit mode")
    elif vars(args)['64']:
        config.archbits = 64
        logger.debug("Forcing 64-bit mode")
    else:
        config.archbits = 64 if platform.architecture()[0] == '64bit' else 32
        logger.debug("Autodetected " + str(config.archbits) + "-bit mode")
    config.monochrome = vars(args)['monochrome']
    if config.monochrome:
        logger.debug("Monochrome output")
    else:
        logger.debug("Colorful output")
    config.verbose = vars(args)['verbose']

def load_core(self, file):
        if os.path.exists(file):
            try:
                core = Core(file)
                self.db.add(core)
            except SyntaxError as e:
                w = "Failed to parse " + file + ": " + e.msg
                pr_warn(w)
                logger.warning(w)
            except ImportError as e:
                pr_warn('Failed to register "{}" due to unknown provider: {}'.format(file, str(e)))

if len(tmp) == 2:
        _name = tmp[1]
    else:
        _name = None
    cls = SECTION_MAP.get(_type)
    if cls is None:
        #Note: The following sections are not in section.py yet
        if not section_name in ['plusargs', 'simulator', 'provider']:
            pr_warn("Unknown section '{}' in '{}'".format(section_name, file_name))
        return None

    items = config.get_section(section_name)
    section = cls(items)
    if section.warnings:
        for warning in section.warnings:
            pr_warn('Warning: %s in %s' % (warning, file_name))
    if _name:
        return (section, _name)
    else:
        return section

f1.write('verilog work ' + src_file.name + '\n')
            elif src_file.file_type in ["vhdlSource",
                                        "vhdlSource-87",
                                        "vhdlSource-93"]:
                f1.write('vhdl work ' + src_file.logical_name + " " + src_file.name + '\n')
            elif src_file.file_type in ['vhdlSource-2008']:
                f1.write('vhdl2008 ' + src_file.logical_name + " " + src_file.name + '\n')
            elif src_file.file_type in ["systemVerilogSource",
                                        "systemVerilogSource-3.0",
                                        "systemVerilogSource-3.1",
                                        "systemVerilogSource-3.1a",
                                        "verilogSource-2005"]:
                f1.write('sv work ' + src_file.name + '\n')
            else:
                _s = "{} has unknown file type '{}'"
                pr_warn(_s.format(src_file.name,
                                  src_file.file_type))
        f1.close()

        tcl_file = 'xsim.tcl'
        f2 = open(os.path.join(self.work_root,tcl_file),'w')
        f2.write('add_wave -radix hex /\n')
        f2.write('run all\n')
        f2.close()

cmd = 'vcom'
                args = ['-87']
            elif f.file_type == 'vhdlSource-93':
                cmd = 'vcom'
                args = ['-93']
            elif f.file_type == 'vhdlSource-2008':
                cmd = 'vcom'
                args = ['-2008']
            elif f.file_type == 'tclSource':
                cmd = None
                tcl_main.write("do {}\n".format(f.name))
            elif f.file_type == 'user':
                cmd = None
            else:
                _s = "{} has unknown file type '{}'"
                pr_warn(_s.format(f.name,
                                  f.file_type))
                cmd = None
            if cmd:
                if not Config().verbose:
                    args += ['-quiet']
                args += ['-work', f.logical_name]
                args += [f.name]
                tcl_build_rtl.write("{} {}\n".format(cmd, ' '.join(args)))