Script for parsing jsons in bash

pjson.py

#!/bin/python
"""
pjson - simple script for parsing jsons with python

Json input needed with stdin. 

Usage:
    pjson key1 key2 key3 ...

Examples:
     $ echo '{ "articles": [ { "title": "Title 1" }, { "title": "Title 3" }, { "title": "Title 3" } ]}' | pjson
     {
         "articles": [
             {
                 "title": "Title 1"
             },
             {
                 "title": "Title 3"
             },
             {
                 "title": "Title 3"
             }
         ]
     }
     
     $ echo '{ "articles": [ { "title": "Title 1" }, { "title": "Title 3" }, { "title": "Title 3" } ]}' | pjson articles                                                                                                                                    [12:10:08]
     [
         {
             "title": "Title 1"
         },
         {
             "title": "Title 3"
         },
         {
             "title": "Title 3"
         }
     ]
     
     echo '{ "articles": [ { "title": "Title 1" }, { "title": "Title 3" }, { "title": "Title 3" } ]}' | pjson articles 0                                                                                                                                  [12:10:30]
     {
         "title": "Title 1"
     }
     
     $ echo '{ "articles": [ { "title": "Title 1" }, { "title": "Title 3" }, { "title": "Title 3" } ]}' | pjson articles 0 title                                                                                                                            [12:10:49]
     "Title 1"
     
     $ echo '{ "articles": [ { "title": "Title 1" }, { "title": "Title 3" }, { "title": "Title 3" } ]}' | pjson articles ... title                                                                                                                          [12:11:02]
     [
         "Title 1",
         "Title 3",
         "Title 3"
     ]     

"""
import sys,json

def main():
	json_obj = json.load(sys.stdin)
	select_all = False
	for arg in sys.argv[1:]:
		if not select_all and isinstance(json_obj, (list, tuple, str, set, )):
			if arg != '...':
				json_obj = json_obj[int(arg)]
			else:
				select_all = True
		else:
			if select_all:
				json_obj = [
					obj[arg] for obj in json_obj
				]
				select_all = False
			else:
				json_obj = json_obj[arg]
	print(json.dumps(json_obj, sort_keys=True, indent=4))

try:
	main()
except KeyboardInterrupt:
	print(__doc__)