from bs4 import BeautifulSoup

def wrap(to_wrap, wrap_in):
    contents = to_wrap.replace_with(wrap_in)
    wrap_in.append(contents)

for obj in Post.objects.all():
    soup = BeautifulSoup(obj.content, 'html.parser')
    for item in soup.children:
        if item.name is None:
            wrap(item, soup.new_tag("p"))

    obj.content = str(soup)
    obj.save()