[Python] RuntimeError: The current Flask app is not registered with this 'SQLAlchemy'...

ERROR : RuntimeError: The current Flask app is not registered with this 'SQLAlchemy' instance. Did you forget to call 'init_app', or did you create multiple 'SQLAlchemy' instances?

i'll be honest, i have no idea what im doing. Heres what i have

base.html


<!DOCTYPE html>
<html lang="es">
<head>
<title>Superhéroes</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
</head>
<body class="container mt-4">
{% block content %}{% endblock %}
</body>
</html>

index.html

{% extends "base.html" %}
{% block content %}
<h1>Lista de Superhéroes</h1>
<a href="{{ url_for('add') }}" class="btn btn-success mb-3">Agregar Superhéroe</a>
<table class="table">
<tr>
<th>Alias</th><th>Nombre Real</th><th>Acciones</th>
</tr>
{% for superheroe in superheroes %}
<tr>
<td>{{ superheroe.alias }}</td>
<td>{{ superheroe.nombre_real }}</td>
<td>
<a href="{{ url_for('edit', id=superheroe.id) }}" class="btn btn-warning">Editar</a>
<a href="{{ url_for('delete', id=superheroe.id) }}" class="btn btn-danger">Eliminar</a>
</td>
</tr>
{% endfor %}
</table>
{% endblock %}


add.html

{% extends "base.html" %}
{% block content %}
<h1>Registrar Superhéroe</h1>
<form method="post">
{{ form.hidden_tag() }}
<p>{{ form.nombre_real.label }} {{ form.nombre_real() }}</p>
<p>{{ form.alias.label }} {{ form.alias() }}</p>
<p>{{ form.foto.label }} {{ form.foto() }}</p>
<p>{{ form.info.label }} {{ form.info() }}</p>
<p>{{ form.submit() }}</p>
</form>
{% endblock %}


edit.html

{% extends "base.html" %}
{% block content %}
<h1>Editar Superhéroe</h1>
<form method="post">
{{ form.hidden_tag() }}
<p>{{ form.nombre_real.label }} {{ form.nombre_real() }}</p>
<p>{{ form.alias.label }} {{ form.alias() }}</p>
<p>{{ form.foto.label }} {{ form.foto() }}</p>
<p>{{ form.info.label }} {{ form.info() }}</p>
<p>{{ form.submit() }}</p>
</form>
{% endblock %}


app.py

from flask import Flask, render_template, redirect, url_for, request
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///database.db'
app.config['SECRET_KEY'] = 'supersecretkey'

db = SQLAlchemy(app)
migrate = Migrate(app, db)

from models import Superheroe

@app.route('/')
def index():
superheroes = Superheroe.query.all()
return render_template('index.html', superheroes=superheroes)

if __name__ == '__main__':
with app.app_context():
db.create_all()
app.run(debug=True)


models.py

from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

class Superheroe(db.Model):
id = db.Column(db.Integer, primary_key=True)
nombre_real = db.Column(db.String(100), nullable=False)
alias = db.Column(db.String(100), nullable=False)
foto = db.Column(db.String(255), nullable=False)
info = db.Column(db.Text, nullable=False)


forms.py

from flask_wtf import FlaskForm
from wtforms import StringField, TextAreaField, SubmitField
from wtforms.validators import DataRequired, URL

class SuperheroeForm(FlaskForm):
nombre_real = StringField('Nombre Real', validators=[DataRequired()])
alias = StringField('Alias', validators=[DataRequired()])
foto = StringField('URL de la Foto', validators=[URL()])
info = TextAreaField('Información Adicional')
submit = SubmitField('Guardar')


I'm so sorry for posting the whole thing, i would really appreciate help

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