Mixer -- Is a fixtures replacement. Supported Django, Flask, SqlAlchemy and custom python objects.

from mixer.backend.django import mixer
from customapp.models import User, UserMessage

# Generate a random user
user = mixer.blend(User)

# Generate an UserMessage
message = mixer.blend(UserMessage, user=user)

# Generate an UserMessage and an User. Set username for generated user to 'testname'.
message = mixer.blend(UserMessage, user__username='testname')

# Generate SomeModel from SomeApp and select FK or M2M values from db
some = mixer.blend('someapp.somemodel', somerelation=mixer.SELECT)

# Generate SomeModel from SomeApp and force a value of money field from default to random
some = mixer.blend('someapp.somemodel', money=mixer.RANDOM)

# Generate 5 SomeModel's instances and take company field's values from custom generator
some_models = mixer.cycle(5).blend('somemodel', company=(name for name in company_names))

from mixer.backend.flask import mixer
from models import User, UserMessage

mixer.init_app(self.app)

# Generate a random user
user = mixer.blend(User)

# Generate an userMessage
message = mixer.blend(UserMessage, user=user)

# Generate an UserMessage and an User. Set username for generated user to 'testname'.
message = mixer.blend(UserMessage, user__username='testname')

# Generate SomeModel and select FK or M2M values from db
some = mixer.blend('project.models.SomeModel', somerelation=mixer.SELECT)

# Generate SomeModel from SomeApp and force a value of money field from default to random
some = mixer.blend('project.models.SomeModel', money=mixer.RANDOM)

# Generate 5 SomeModel's instances and take company field's values from custom generator
some_models = mixer.cycle(5).blend('project.models.SomeModel', company=(company for company in companies))

from mixer.backend.sqlalchemy import Mixer

class MyOwnMixer(Mixer):

    def populate_target(self, values):
        target = self.__scheme(**values)
        return target

mixer = MyOwnMixer()

from mixer.backend.sqlalchemy import Mixer

ENGINE = create_engine('sqlite:///:memory:')
BASE = declarative_base()
SESSION = sessionmaker(bind=ENGINE)

mixer = Mixer(session=SESSION(), commit=True)
role = mixer.blend('package.models.Role')

from mixer.backend.mongoengine import mixer

class User(Document):
    created_at = DateTimeField(default=datetime.datetime.now)
    email = EmailField(required=True)
    first_name = StringField(max_length=50)
    last_name = StringField(max_length=50)
    username = StringField(max_length=50)

class Post(Document):
    title = StringField(max_length=120, required=True)
    author = ReferenceField(User)
    tags = ListField(StringField(max_length=30))

post = mixer.blend(Post, author__username='foo')

from mixer.backend.marshmallow import mixer
import marshmallow as ma

class User(ma.Schema):
    created_at = ma.fields.DateTime(required=True)
    email = ma.fields.Email(required=True)
    first_name = ma.fields.String(required=True)
    last_name = ma.fields.String(required=True)
    username = ma.fields.String(required=True)

class Post(ma.Schema):
    title = ma.fields.String(required=True)
    author = ma.fields.Nested(User, required=True)

post = mixer.blend(Post, author__username='foo')

from mixer.main import mixer

class Test:
    one = int
    two = int
    name = str

class Scheme:
    name = str
    money = int
    male = bool
    prop = Test

scheme = mixer.blend(Scheme, prop__one=1)

from mixer.backend.django import Mixer

mixer = Mixer(commit=False)

from mixer.backend.django import mixer

# Will be save to db
user1 = mixer.blend('auth.user')

# Will not be save to db
with mixer.ctx(commit=False):
    user2 = mixer.blend('auth.user')

from mixer.main import mixer

class Test:
    id = int
    name = str

mixer.register(Test,
    name=lambda: 'John',
    id=lambda: str(mixer.faker.small_positive_integer())
)

test = mixer.blend(Test)
test.name == 'John'
isinstance(test.id, str)

# You could pinned just a value to field
mixer.register(Test, name='Just John')
test = mixer.blend(Test)
test.name == 'Just John'

from mixer.backend.django import Mixer, GenFactory

def get_func(*args, **kwargs):
    return "Always same"

class MyFactory(GenFactory):
    generators = {
        models.CharField: get_func
    }

mixer = Mixer(factory=MyFactory)

from mixer.backend.django import mixer

# Register middleware to model
@mixer.middleware('auth.user')
def encrypt_password(user):
    user.set_password('test')
    return user

mixer.unregister_middleware(encrypt_password)

from mixer.backend.django import Mixer

mixer = Mixer(locale='it')
mixer.faker.name()          ## u'Acchisio Conte'

mixer.faker.locale = 'cz'
mixer.faker.name()          ## u'Miloslava Urbanov\xe1 CSc.'

mixer.faker.locale = 'en'
mixer.faker.name()          ## u'John Black'

# Use the mixer context manager
mixer.faker.phone()         ## u'1-438-238-1116'
with mixer.ctx(locale='fr'):
    mixer.faker.phone()     ## u'08 64 92 11 79'

mixer.faker.phone()         ## u'1-438-238-1116'