How to use the flasgger.APISpec function in flasgger

"""
Example using marshmallow APISpec as base template for Flasgger specs
and using the Swagger UI new style layout version 3
"""
# coding: utf-8
from flask import Flask, jsonify

from flasgger import APISpec, Schema, Swagger, fields
from apispec.ext.marshmallow import MarshmallowPlugin
from apispec_webframeworks.flask import FlaskPlugin

# Create an APISpec
spec = APISpec(
    title='Flasger Petstore',
    version='1.0.10',
    openapi_version='2.0',
    plugins=[
        FlaskPlugin(),
        MarshmallowPlugin(),
    ],
)

app = Flask(__name__)


# Optional marshmallow support
class CategorySchema(Schema):
    id = fields.Int()
    name = fields.Str(required=True)

from .account import account as account_blueprint
    app.register_blueprint(account_blueprint, url_prefix='/account')

    from .api.auth import auth as auth_blueprint
    app.register_blueprint(auth_blueprint, url_prefix='/auth')

    from .admin import admin as admin_blueprint
    app.register_blueprint(admin_blueprint, url_prefix='/admin')

    from app.api.docs import docs as docs_blueprint
    app.register_blueprint(docs_blueprint)

    from flasgger import APISpec, Schema, Swagger, fields

    spec = APISpec(
        title='Bhagavad Gita API',
        version='1.0.0',
        plugins=[
            'apispec.ext.flask',
            'apispec.ext.marshmallow',
        ],
    )

    app.config['SWAGGER'] = {'title': 'Bhagavad Gita API', 'uiversion': 3}

    swagger = Swagger(
        app,
        template={
            'swagger': '2.0',
            'info': {
                'title': 'Bhagavad Gita API',

"""
Example using marshmallow APISpec as base template for Flasgger specs
"""
# coding: utf-8
from flask import Flask, jsonify

from flasgger import APISpec, Schema, Swagger, fields
from apispec.ext.marshmallow import MarshmallowPlugin
from apispec_webframeworks.flask import FlaskPlugin

# Create an APISpec
spec = APISpec(
    title='Flasger Petstore',
    version='1.0.10',
    openapi_version='2.0',
    plugins=[
        FlaskPlugin(),
        MarshmallowPlugin(),
    ],
)

app = Flask(__name__)


# Optional marshmallow support
class CategorySchema(Schema):
    id = fields.Int()
    name = fields.Str(required=True)