You could use the function html.unescape:
In Python3.4+ (thanks to J.F. Sebastian for the update):
import html
html.unescape('Suzy & John')
# 'Suzy & John'
html.unescape('"')
# '"'
In Python3.3 or older:
import html.parser
html.parser.HTMLParser().unescape('Suzy & John')
In Python2:
import HTMLParser
HTMLParser.HTMLParser().unescape('Suzy & John')
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