How to create Article tags from splitting the Title in Django

I want to create articles tags from the title of a RSS feed post. Then save the tags into a DB with a post_id of the title i got the tags from at the same time. Something like this:

Title = "Voyant raises $15M to scale production of its tiny, inexpensive lidar tech"Tags = ['Voyant', 'Raises', '$15M', 'To', 'Scale', 'Production', 'Of', 'Its', 'Tiny', 'Inexpensive', 'Lidar', 'Tech']

Assuming the post_id is 1, the Tags table should look like:

id    |    tag     |   post_id-------------------------------- 1    |  Voyant    |      1 2    |  Raises    |      1

I have 3 models in my table(Source, Posts & Tags).

class Source(models.Model):    name = models.CharField(max_length=500, verbose_name='Website Name')class Posts(models.Model):    post_title = models.CharField(max_length=500, verbose_name='Post Title')    source = models.ForeignKey(Source, on_delete=models.CASCADE, verbose_name='Source')class Tags(models.Model):    name = models.CharField(max_length=500)    post = models.ForeignKey(Posts, on_delete=models.CASCADE, verbose_name='Posts')

So so far i was able to split the title above.

title = item.titlestrip_away = title.replace(",", "").replace(":", "").replace("(", "").replace(")", "").replace("'", "").replace("[", "").replace("]", "").replace("!", "").replace("?", "").replace("-", " ")capital = strip_away.title()article_tags = capital.split()

But now my problem comes during the saving part.

def fetch_articles():    feed = feedparser.parse("my_site_of_preference")    source = Source.objects.get(pk=1)    source_id = int(source.pk)    source_name = source    save_new_articles(source_id, source_name, feed)def save_new_articles(source_id, source_name, feed):   selected_source_id = source_id   for item in feed.entries:       title = item.title""" The splitting code """      if not Posts.objects.filter(post_title=title).exists():         post = Posts(post_title = title, source_id = selected_source_id)         post.save()      for i in range(len(article_tags)):          tags = Tags.objects.create(name = article_tags[i], post_id = source_name.pk)          tags.save()

I keep getting the error:

django.db.utils.IntegrityError: insert or update on table "Posts_tags" violates foreign key constraint "Posts_tags_post_id_3e6ae939_fk_Posts_posts_id"DETAIL:  Key (post_id)=(1) is not present in table "Posts_posts".

The post hasn't been saved to create a post_id that it can be used as a PK when saving the tags. How can i go about this to save the tags after saving the post title?