How to import an object of one app into another app in the same django project?

Codes are given below.

users.model.py

from django.contrib.auth.models import AbstractBaseUser, PermissionsMixin
from django.db import models
from django.utils import timezone
from django.utils.translation import gettext_lazy as _
from django.db import models
# from django.contrib.auth.models import User
from PIL import Image


from .managers import CustomUserManager

from django.contrib import admin

from django.contrib.auth.models import AbstractUser
from django.utils.translation import ugettext_lazy as _


class CustomUser(AbstractUser):
    username = None
    first_name = models.CharField('Name',max_length=200,unique=True)
    email = models.EmailField(_('email address'), unique=True)
    registration = models.IntegerField()
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []

    objects = CustomUserManager()

    def __str__(self):
        return self.email



class Profile(models.Model):
    user = models.OneToOneField(CustomUser, on_delete=models.CASCADE)
    image = models.ImageField(default='default.jpg', upload_to='profile_pics')

blog.model.py

from django.db import models
from django.utils import timezone
from django.urls import reverse
from django.conf import settings
from multiselectfield import MultiSelectField

from django import forms
from django.core.validators import MinValueValidator, MaxValueValidator
from PIL import Image




DAYS_OF_WEEK = [
    (0, '  Monday'),
    (1, '  Tuesday'),
    (2, '  Wednesday'),
    (3, '  Thursday'),
    (4, '  Friday'),
    (5, '  Saturday'),
    (6, '  Sunday'),
]



class PostManager(models.Manager):
    def like_toggle(self, user, post_obj):
        if user in post_obj.liked.all():
            is_liked = False
            post_obj.liked.remove(user)
        else:
            is_liked = True
            post_obj.liked.add(user)
        return is_liked



class Post(models.Model):
    author = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    title = models.CharField('Doctor\'s Name',max_length=100)
    content = models.CharField('Specialty',max_length=100)
    chamber = models.CharField('Chamber\'s Name',max_length=200)
    address = models.CharField('Address',max_length=100, blank=True)
    fees = models.IntegerField(default=0)

    days = MultiSelectField('Available Days', choices= DAYS_OF_WEEK)

    start_time = models.TimeField('Chamber Beginning Time')
    end_time = models.TimeField('Chamber Ending Time')
    image = models.ImageField( upload_to='profile_pics')
    review = models.TextField()

    rating = models.IntegerField('Behavior')
    overall_rating = models.PositiveIntegerField(validators=[
            MaxValueValidator(10),
            MinValueValidator(0)
        ])


    liked = models.ManyToManyField(
        settings.AUTH_USER_MODEL, blank=True, related_name='liked')
    date_posted = models.DateTimeField(default=timezone.now)

    objects = PostManager()

    class Meta:
        ordering = ('-date_posted', )

    def get_absolute_url(self):
        return reverse('post_detail', kwargs={'pk': self.pk})

    def save(self):
        super().save()  # saving image first

        img = Image.open(self.image.path) # Open image using self

        if (img.height > 1020 or img.width > 1920):
            new_img = (1020, 1920)
            img.thumbnail(new_img)
            img.save(self.image.path)  # saving image at the same path


class Comment(models.Model):
    post = models.ForeignKey(
        Post, related_name='comments', on_delete=models.CASCADE)
    author = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    text = models.TextField()
    created_date = models.DateTimeField(default=timezone.now)
    approved_comment = models.BooleanField(default=True)

    def approve(self):
        self.approved_comment = True
        self.save()

    def get_absolute_url(self):
        return reverse("post_list")

    def __str__(self):
        return self.author

I have created a project. In that project there are two apps named: user and blog. I’m saving the CustomUsers in Profile.
I want to use the user.model.py file’s first_name field value as blog.model.py file’s title field.
I’m new to django.Help me fix this issue!