bigger

$ dig -t txt foo2.example.net @127.0.0.1

; <<>> DiG 9.11.2 <<>> -t txt foo2.example.net @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62695
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1680
;; QUESTION SECTION:
;foo2.example.net.		IN	TXT

;; ANSWER SECTION:
foo2.example.net.	3600	IN	TXT	"{\"glossary\":{\"title\":\"example glossary\",\"GlossDiv\":{\"title\":\"S\",\"GlossList\":{\"GlossEntry\":{\"ID\":\"SGML\",\"SortAs\":\"SGML\",\"GlossTerm\":\"Standard Generalized Markup Language\",\"Acronym\":\"SGML\",\"Abbrev\":\"ISO 8879:1986\",\"GlossDef\":{\"para\":\"A meta-markup language," " used to create markup languages such as DocBook.\",\"GlossSeeAlso\":[\"GML\",\"XML\"]},\"GlossSee\":\"markup\"}}}}}"

;; Query time: 5 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Mar 16 15:16:15 CET 2018
;; MSG SIZE  rcvd: 419

>>> import dns.name, dns.message, dns.query
>>> qname = dns.name.from_text('foo2.example.net'); q = dns.message.make_query(qname, dns.rdatatype.TXT); r = dns.query.udp(q, '127.0.0.1')
>>> txt=r.find_rrset(r.answer, qname, dns.rdataclass.IN, dns.rdatatype.TXT)
>>> txt[0].strings
[b'{"glossary":{"title":"example glossary","GlossDiv":{"title":"S","GlossList":{"GlossEntry":{"ID":"SGML","SortAs":"SGML","GlossTerm":"Standard Generalized Markup Language","Acronym":"SGML","Abbrev":"ISO 8879:1986","GlossDef":{"para":"A meta-markup language,', b' used to create markup languages such as DocBook.","GlossSeeAlso":["GML","XML"]},"GlossSee":"markup"}}}}}']
>>> b''.join(txt[0].strings)
b'{"glossary":{"title":"example glossary","GlossDiv":{"title":"S","GlossList":{"GlossEntry":{"ID":"SGML","SortAs":"SGML","GlossTerm":"Standard Generalized Markup Language","Acronym":"SGML","Abbrev":"ISO 8879:1986","GlossDef":{"para":"A meta-markup language, used to create markup languages such as DocBook.","GlossSeeAlso":["GML","XML"]},"GlossSee":"markup"}}}}}'
>>> import json
>>> json.loads(b''.join(txt[0].strings))
{'glossary': {'title': 'example glossary', 'GlossDiv': {'title': 'S', 'GlossList': {'GlossEntry': {'ID': 'SGML', 'SortAs': 'SGML', 'GlossTerm': 'Standard Generalized Markup Language', 'Acronym': 'SGML', 'Abbrev': 'ISO 8879:1986', 'GlossDef': {'para': 'A meta-markup language, used to create markup languages such as DocBook.', 'GlossSeeAlso': ['GML', 'XML']}, 'GlossSee': 'markup'}}}}}
>>>

dig

$ dig +short -t txt foo.example.net @127.0.0.1
"{\"hi\":5}"

txt-with-args.py

#!/usr/bin/env python
import sys
import dns.name, dns.message, dns.query
qname = dns.name.from_text(sys.argv[1]); q = dns.message.make_query(qname, dns.rdatatype.TXT); r = dns.query.udp(q, sys.argv[2])
txts=r.find_rrset(r.answer, qname, dns.rdataclass.IN, dns.rdatatype.TXT)
for txt in txts:
	print(b''.join(txt.strings).decode('ascii'))

txt.py

>>> import dns.name, dns.message, dns.query
>>> qname = dns.name.from_text('foo.example.net'); q = dns.message.make_query(qname, dns.rdatatype.TXT); r = dns.query.udp(q, '127.0.0.1')
>>> txt=r.find_rrset(r.answer, qname, dns.rdataclass.IN, dns.rdatatype.TXT)
>>> txt[0].strings
[b'{"hi":5}']

usage

$ ./txt.py foo2.example.net 127.0.0.1 | jq .
{
  "glossary": {
    "title": "example glossary",
    "GlossDiv": {
      "title": "S",
      "GlossList": {
        "GlossEntry": {
          "ID": "SGML",
          "SortAs": "SGML",
          "GlossTerm": "Standard Generalized Markup Language",
          "Acronym": "SGML",
          "Abbrev": "ISO 8879:1986",
          "GlossDef": {
            "para": "A meta-markup language, used to create markup languages such as DocBook.",
            "GlossSeeAlso": [
              "GML",
              "XML"
            ]
          },
          "GlossSee": "markup"
        }
      }
    }
  }
}