from app import db

class Example(db.Model):
    __tablename__ = 'example'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    image = db.Column(db.LargeBinary)
    description = db.Column(db.String(120))

example.image = request.json['image']

sqlalchemy.exc.StatementError: (builtins.TypeError) memoryview: a bytes-like object is required, not 'str' [SQL: 'INSERT INTO example (image, description) VALUES (?, ?)'] [parameters: [{'image':''iVBORw0KGgoAAAANSUhEUgAAASwAAACWCAYAAABkW7XSAAAgAElEQVR4Xkyd65Ikx5GdI+9ZWVXdMwOQMtPF9EM/dDEtd0GQS4LgLk2m938KmWklApjprlveM/V9XsM1cUURmOmuyozwcD9+/LhH9 ... (131066 characters truncated) ... U+bq1fYzK8CjL+Htr9jmjGZaL/sAccUiPf8/8906GpLwkQngOCuh5nohrdndHTRHii8Q55Rlk2N1B1ZGCCmSIct5gm/IiAAAAEklEQVSsvzbg3YTp3ut72d+/AvI8T5jSrxmzAAAAAElFTkSuQmCC'','description':'Example description'}]]

request.json['image'].encode('utf-8')