def __init__(self, parent: str, content_filename: str | None=None):
    """Create the header node.

    :param parent: (str) The parent node identifier
    :param content_filename: (str) The HTML content filename

    """
    super(WhakerKitHeaderNode, self).__init__(parent)
    self.reset(content_filename)
    self.set_attribute('id', 'header-content')

def reset(self, filename: str | None=None):
    """Reset the header to its default values.

        :param filename: (str | None) The filename to use for the header content

        """
    self.clear_children()
    a = HTMLNode(self.identifier, None, 'a', value=get_msg(MSG_SKIP))
    a.set_attribute('role', 'button')
    a.set_attribute('class', 'skip')
    a.set_attribute('href', '#main-content')
    self.append_child(a)
    if filename is not None and os.path.exists(filename) is True:
        with open(filename, encoding='utf-8') as html_file:
            content = html_file.read()
            if len(content.strip()) > 0:
                self.set_value(content.strip())
    nav = WhakerKitAccessibilityNavNode(self.identifier)
    self.append_child(nav)