from bs4 import BeautifulSoup
s = "<blockquote><i>Quote</i></blockquote><br />text <h3>This is a title</h3>"
soup = BeautifulSoup(s, "html.parser")
soup_all =  soup.findAll()
for s in soup.strings:
    print get_tags_by_string(s)

Quote -> blockquote & i
text -> None
This is a title -> h3