Python Marshmallow AttributeError: 'list' object has no attribute 'get' - python-3.x

Question

I have this schema
from marshmallow import validate, ValidationError
from marshmallow_jsonapi import fields
from marshmallow_jsonapi.flask import Relationship, Schema
class UserSchema(Schema):
first_name = fields.Str(required=True])
last_name = fields.Str(required=True)
title = fields.Str(required=True)
class Meta:
type_ = 'users'
self_view = "blog_view.users_detail"
self_view_kwargs = {"user_id": "<id>", "_external": True}
self_view_many = "blog_view.users_list"
blog= Relationship(
many=False,
include_data=True,
type_="blogs",
include_resource_linkage=True,
schema="BlogSchema"
)
I want to load this data(coming from UI) for validation:
bulk_data = [
{ 'type': 'users',
'relationships': {'blog': {'data': {'type': 'blogs', 'id': blog_id}}},
{'first_name': 'Billy', 'last_name': 'Butcher', 'title': 'Supe Hunter'}
},
{ 'type': 'users',
'relationships': {'blog': {'data': {'type': 'blogs', 'id': blog_id}}},
{'first_name': 'Home', 'last_name': 'Lander', 'title': 'Leader'}
},
{ 'type': 'users',
'relationships': {'blog': {'data': {'type': 'blogs', 'id': blog_id}}},
{'first_name': 'Black', 'last_name': 'Noir', 'title': 'Super Ninja'}
}
]
For validation I did:
data = UserSchema(many=True).load(input_data)
I get an error saying,
AttributeError: 'list' object has no attribute 'get'
which is obvious because I'm passing a list. The validation works fine when I pass a single dictionary from the above list, but I want to pass the bulk data and do validation at once as shown in Marshmallow doc: https://marshmallow.readthedocs.io/en/stable/quickstart.html#validation
When
many=True
, load method expects a collection type so list, tuple, queryset etc.
Any suggestion on how to validate a list of data in Marshmallow? The marshmallow versions are:
marshmallow==2.18.0
marshmallow-jsonapi==0.23.1
Thanks!