Quick and dirty method of making walls of text JSON files indented properly (note, not standards and tab width compliant, just easier to read).

jsondentation.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

from __future__ import absolute_import, division, unicode_literals

# Copyright (C) 2018 Ben McGinnes <ben@gnupg.org>
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU Lesser General Public License as published by the Free
# Software Foundation; either version 2.1 of the License, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License and the GNU
# Lesser General Public Licensefor more details.
#
# You should have received a copy of the GNU General Public License and the GNU
# Lesser General Public along with this program; if not, see
# <http://www.gnu.org/licenses/>.

import json
import pprint
import shutil
import sys

"""
Description: will read the JSON file and rewrite it with
indentationand decent formatting (but no word wrap).  The
original file will be moved to <filename>.bak.
"""

print("""
Usage: jsondentation.py <filename>
""")

if len(sys.argv) < 2:
    print("You must enter a filename.")
elif len(sys.argv) >= 2:
    files = sys.argv[1:]
    for i in range(len(files)):
        filename = files[i]
        bakfile = "{0}.bak".format(filename)
        with open(filename, "rb") as f:
            fn0 = f.read()
        fn1 = json.loads(fn0)
        fn2 = pprint.pformat(fn1)
        shutil.move(filename, bakfile)
        with open(filename, "w") as f:
            f.write(fn2)
else:
    pass