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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def increase_posts_count(sender, instance, **kwargs):
 """ Increases the member's post count after a post save. This receiver handles the update of the profile related to the user who is the poster of the forum post being created or updated. """


    if instance.poster is None:
        # An anonymous post is considered. No profile can be updated in
        # that case.
        return

    profile, dummy = ForumProfile.objects.get_or_create(user=instance.poster)
    increase_posts_count = False

    if instance.pk:
        try:
            old_instance = instance.__class__._default_manager.get(pk=instance.pk)
        except ObjectDoesNotExist:  # pragma: no cover
            # This should never happen (except with django loaddata command)
            increase_posts_count = True
            old_instance = None
        if old_instance and old_instance.approved is False and instance.approved is True:
            increase_posts_count = True
    elif instance.approved:
        increase_posts_count = True

    if increase_posts_count:
        profile.posts_count = F('posts_count') + 1
        profile.save()