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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 create_placeholder(self, slot="blog_contents", role='m', title=None):
 """ Create a placeholder on this blog entry. To fill the content items, use :func:`ContentItemModel.objects.create_for_placeholder() <fluent_contents.models.managers.ContentItemManager.create_for_placeholder>`. :rtype: :class:`~fluent_contents.models.Placeholder` """

        return Placeholder.objects.create_for_object(self, slot, role=role, title=title)