Python flask error, ImportError: DLL load failed.

from flask import Flask, render_template, request, redirect
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///posts.db'
db = SQLAlchemy(app)

class BlogPost(db.Model):
    id = db.Column(db.Integer, primary_key = True)
    title = db.Column(db.String(100), nullable = False) #nullable title musi być podany 
    content = db.Column(db.Text, nullable = False)
    author = db.Column(db.String(20), nullable = False, default = 'N/A')
    date_posted = db.Column(db.DateTime, nullable = False, default = datetime.utcnow)

    def __repr__(self):
        return 'Blog post ' + str(self.id)

all_posts = [
    {
        'title':'Post 1',
        'content':'This is a content of Post 1. LAlalalalALLAa',
        'author':'Pablo'
    },
    {
        'title':'Post 2',
        'content':'This is a content of Post 2. LAlalalalALLAa'

    }
]

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/posts', methods = ['GET', 'POST'])
def posts():

    if request.method == 'POST':
        post_title = request.form['title']
        post_content = request.form['content']
        post_author = request.form['author']
        new_post = BlogPost (title = post_title, content = post_content, author = post_author)
        db.session.add(new_post)
        db.session.commit()
        return redirect('/posts')
    else:
        all_posts = BlogPost.query.order_by(BlogPost.date_posted).all()
        return render_template('posts.html', posts = all_posts)

@app.route('/home/users/<string:name>/posts/<int:id>')
def hello(name, id):
    return 'Hello ' + name + ', youre id is: ' + str(id)

@app.route('/onlyget', methods = ['GET'])
def get_req():
    return 'you can get this webpage.'


if __name__ == '__main__':
    app.run(debug = True)