Stuck on error with ForeignKeyField

I am trying to follow along with the post model steps for the Social App. I'm doing it in VS Code because I want the benefits of more up-to-date code and extension. So far so good, but I've hit an error I can't seem to figure out.

Firstly let me post the error message:

Traceback (most recent call last):
  File "app.py", line 8, in <module>
    import forms
  File "D:\Dropbox\Coding Projects\#######\forms.py", line 6, in <module>
    from models import User
  File "D:\Dropbox\Coding Projects\#######\models.py", line 45, in <module>
    class Post(Model):
  File "D:\Dropbox\Coding Projects\#######\models.py", line 47, in Post
    user = ForeignKeyField(
TypeError: __init__() missing 1 required positional argument: 'model'

If I'm correct, the error is referring to the ForeignKeyField in my Post class? I have rewatched the videos, checked the syntax, scoured stackoverflow and looked at the WTForms & Flask docs. But I can't seem to find what's wrong. Hence the post.

Below is my code that seems to be throwing the error:

class Post(Model):
    timestamp = DateTimeField(default=datetime.datetime.now)
    user = ForeignKeyField(
        rel_model=User,
        related_name='posts'
    )
    content = TextField()

    class Meta:
        database = DATABASE
        order_by = ('-timestamp',)

What I can say, is that if I comment out the user variable part, the app then loads and runs as expected (up to the part where it needs to submit the post.).

Part of me is wondering whether this is a database issue. It seems to me like maybe the form is not able to submit the post because it doesn't have the relevant tables to post too.

The below piece of code obviously creates the User table but how is the Post table created to store the posts?

def initialize():
    DATABASE.connect()
    DATABASE.create_tables([User], safe=True)
    DATABASE.close()

Any clues or help would be greatly appreciated. :)