main code for blog in fasthtml

main.py

from fasthtml.common import *
from monsterui.all import *
from helpers import Post, get_posts_by_language, DEFAULT_LANG, get_post
app, rt = fast_app(hdrs=Theme.zinc.headers(highlightjs=True), debug=True, live=True)
posts_by_lang = get_posts_by_language()

def lang_str(lang: str): return "🇫🇷 FR" if lang == "fr" else "🇬🇧 EN"

def render_dropdown_language_post(post: Post):
    return Form(Select((Option(lang_str(lang), value=lang, selected=lang == post.metadata["language"]) for lang in ["en", "fr"]), cls="flex justify-end", hx_post="/setlanguage",
                  name="lang"),
                  Hidden(value=post.metadata["slug"], name="slug"),
                  hx_target="#post-container",
                  hx_trigger="change")

def render_post(post: Optional[Post]):
    if not post: return Container(
        Div(
            H1("Post not found", cls="text-4xl font-bold mb-8 text-center pt-4"),
            cls="max-w-3xl mx-auto px-4"
        )
    )
    return Container(
        Div(
            Div(
                render_dropdown_language_post(post),
                H1(post.metadata["title"], cls="text-3xl font-bold mb-4"),
                P(post.metadata["description"], cls="text-gray-600 mb-6"),
                cls="bg-gray-50 p-6 rounded-t-lg"
            ),
            Div(render_md(post.content), cls="p-6"),
            cls="border rounded-lg shadow-sm  mx-auto"
        ),
        id="post-container",
    )

def get_card_post(post: Post):
    return A(
        Div(
            H2(post.metadata["title"], cls="text-2xl font-semibold hover:text-blue-600"),
            P(post.metadata["description"], cls="text-gray-600 mt-2"),
            Div(
                P(f"By {post.metadata['author']}", cls="text-sm text-gray-500"),
                P(f"Posted on {post.metadata['date']}", cls="text-sm text-gray-500"),
                cls="flex gap-4 mt-1"
            ),
            Div(*(
                Span(tag, cls="px-2 py-1 text-xs bg-gray-100 rounded")
                for tag in post.metadata["tags"]
            ), cls="flex gap-2 mt-2"),
            cls="p-6 border rounded-lg hover:shadow-lg transition-shadow duration-200 mb-4"
        ),
        href=f"/posts/{post.metadata['slug']}",
        cls="block no-underline"
    )



def nav():
    return NavBar(
        nav_links=[
            A("Blogs", href="/posts"),
            A("About", href="/"),
        ],
        title=H3("Simon Moisselin's Blog"),
    )

@app.get("/")
def about():
    return Container(
        nav(),
        Div(
            H1("About Me", cls="text-4xl font-bold mb-8 text-center pt-4"),
            P("Hi, I'm Simon Moisselin. I write about Python, web development and other tech topics.",
              cls="text-gray-600 mb-4 text-center"),
            cls="max-w-3xl mx-auto px-4"
        )
    )

@app.get("/posts")
def home(session):
    posts = posts_by_lang[session.get('language', DEFAULT_LANG)]
    return (
        nav(),
        Div(
            H1("Blog of Simon Moisselin", cls="text-4xl font-bold mb-8 text-center pt-4"),
            P("Made with FastHTML", cls="text-gray-600 mb-8 text-center"),
            Div(*(get_card_post(post) for post in posts), cls="space-y-6"),
            cls="max-w-3xl mx-auto px-4"
        )
    )


@app.get("/posts/{slug}")
def post(session, slug: str):
    post = get_post(slug, session.get('language', DEFAULT_LANG), posts_by_lang)
    return (
        nav(),
        render_post(post)
    )


@app.post("/setlanguage")
def set_language(session, lang: str, slug: str):
    session['language'] = lang
    return render_post(get_post(slug, lang, posts_by_lang))

serve()

Hey, your automatic translation system is very cool. I would like to implement something similar. Could you share the helpers functions. Which I assume are some other code of you.
Thank you very much.