read a html file and print body content as json escaped string including html

escape_html_body_to_json.py

#!/usr/bin/python3
import sys
import json
import html
from escapejson import escapejson
from lxml import etree
import lxml.html
from io import StringIO, BytesIO

with open(str(sys.argv[1]),'r') as f:
    ret = f.read()

# print(html)
# root = lxml.html.fromstring(html)
parser = etree.HTMLParser()
tree = etree.parse(StringIO(ret), parser)
root = tree.getroot()
ret = etree.tostring(root.find('body')).decode('utf-8')
start = ret.find('>') +1
end = ret.find('</body>')
ret = ret[start:end]
ret = html.unescape(ret)
ret = json.dumps(ret)
ret = escapejson(ret)

print(ret)