How to use the peru.error.PrintableError function in peru

def find_project_file(start_dir, basename):
    '''Walk up the directory tree until we find a file of the given name.'''
    prefix = os.path.abspath(start_dir)
    while True:
        candidate = os.path.join(prefix, basename)
        if os.path.isfile(candidate):
            return candidate
        if os.path.exists(candidate):
            raise PrintableError(
                "Found {}, but it's not a file.".format(candidate))
        if os.path.dirname(prefix) == prefix:
            # We've walked all the way to the top. Bail.
            raise PrintableError("Can't find " + basename)
        # Not found at this level. We must go...shallower.
        prefix = os.path.dirname(prefix)

def _error(logging_target_name, text, *text_format_args):
    text = text.format(*text_format_args)
    raise PrintableError('Error in target {}: {}'.format(
        logging_target_name, text))

pass


class PluginCommandCandidateError(PrintableError):
    pass


class PluginModuleFieldError(PrintableError):
    pass


class PluginMetadataMissingError(PrintableError):
    pass


class PluginPermissionsError(PrintableError):
    pass


class PluginRuntimeError(PrintableError):
    def __init__(self, type, fields, errorcode, output):
        # Don't depend on plugins using terminating newlines.
        stripped_output = output.strip('\n')
        super().__init__(stripped_output)

def _get_override_tree(runtime, module, rules):
    override_path = runtime.get_override(module.name)
    if not os.path.exists(override_path):
        raise PrintableError(
            "override path for module '{}' does not exist: {}".format(
                module.name, override_path))
    if not os.path.isdir(override_path):
        raise PrintableError(
            "override path for module '{}' is not a directory: {}".format(
                module.name, override_path))
    override_module = module.get_local_override(override_path)
    tree = yield from override_module.get_tree(runtime, rules)
    return tree

pass


class PluginModuleFieldError(PrintableError):
    pass


class PluginMetadataMissingError(PrintableError):
    pass


class PluginPermissionsError(PrintableError):
    pass


class PluginRuntimeError(PrintableError):
    def __init__(self, type, fields, errorcode, output):
        # Don't depend on plugins using terminating newlines.
        stripped_output = output.strip('\n')
        super().__init__(stripped_output)

@contextlib.contextmanager
def debug_parallel_count_context():
    global DEBUG_PARALLEL_COUNT, DEBUG_PARALLEL_MAX
    DEBUG_PARALLEL_COUNT += 1
    DEBUG_PARALLEL_MAX = max(DEBUG_PARALLEL_COUNT, DEBUG_PARALLEL_MAX)
    try:
        yield
    finally:
        DEBUG_PARALLEL_COUNT -= 1


def tmp_dir(context):
    return tempfile.TemporaryDirectory(dir=context.tmp_root)


class PluginCandidateError(PrintableError):
    pass


class PluginCommandCandidateError(PrintableError):
    pass


class PluginModuleFieldError(PrintableError):
    pass


class PluginMetadataMissingError(PrintableError):
    pass


class PluginPermissionsError(PrintableError):

def _get_module_checked(self, name):
        if name not in self.modules:
            raise PrintableError('Module "{}" doesn\'t exist.', name)
        return self.modules[name]

def _get_override_tree(self, runtime, path):
        if not os.path.exists(path):
            raise PrintableError(
                "override path for module '{}' does not exist: {}".format(
                    self.name, path))
        if not os.path.isdir(path):
            raise PrintableError(
                "override path for module '{}' is not a directory: {}".format(
                    self.name, path))
        return runtime.cache.import_tree(path)

def get_rules(runtime, rule_names):
    rules = []
    for name in rule_names:
        if name not in runtime.scope:
            raise PrintableError('rule "{}" does not exist'.format(name))
        rule = runtime.scope[name]
        # Avoid a circular import.
        if type(rule).__name__ != 'Rule':
            raise PrintableError('"{}" is not a rule'.format(name))
        rules.append(rule)
    return rules