{
    "q1": {
        "type": "multiple", 
        "question": "\n<p>Given the following Python script, <tt>echo.py</tt>:</p>\n\n<pre>\n#!/usr/bin/env python3\n\nimport sys\n\nfor arg in sys.argv[1:]:\n    print(arg)\n</pre>\n\n<p>Which of the following statements are true (select all that apply)?</p>\n", 
        "responses": {
            "print": "It is not necessary to include the parentheses in the <tt>print</tt> function.", 
            "first": "Due to the <tt>[1:]</tt>, the script only prints out the first argument.", 
            "module": "The line <tt>import sys</tt> loads the <tt>sys</tt> Python module.", 
            "argv": "The command-line arguments to the script are stored in <tt>sys.argv</tt>.", 
            "arg": "The <tt>arg</tt> variable needs a <tt>$</tt> in front of it just like in shell."
        }
    }, 
    "q3": {
        "type": "multiple", 
        "question": "\n<p>Given the following Python script, <tt>cat.py</tt>:</p>\n\n<pre>\n#!/usr/bin/env python3\n\nimport os\nimport sys\n\n# Global Variables\n\nENDING = ''\n\n# Usage function\n\ndef usage(status=0):\n    print('''Usage: {} files...\n\n    -E  display $ at end of each line'''.format(os.path.basename(sys.argv[0])))\n    sys.exit(status)\n\n# Parse command line options\n\nargs = sys.argv[1:]\nwhile len(args) and args[0].startswith('-') and len(args[0]) > 1:\n    arg = args.pop(0)\n    if arg == '-E':\n        ENDING = '$'\n    elif arg == '-h':\n        usage(0)\n    else:\n        usage(1)\n\nif len(args) == 0:\n    args.append('-')\n\n# Main execution\n\nfor path in args:\n    if path == '-':\n        stream = sys.stdin\n    else:\n        stream = open(path)\n\n    for line in stream:\n        line = line.rstrip()\n        print(line + ENDING)\n\n    stream.close()\n</pre>\n\n<p>Which of the following statements are true (select all that apply)?</p>\n", 
        "responses": {
            "status": "If the <tt>usage</tt> function is called without an argument, that would result in an error.", 
            "startswith": "The <tt>args[0].startswith('-')</tt> checks if the first argument begins with the character <tt>-</tt>.", 
            "basename": "The <tt>os.path.basename</tt> function returns the directory of the specified path.", 
            "stdin": "If no argument is passed to the script, then <tt>sys.stdin</tt> will be read.", 
            "len": "The <tt>len</tt> function returns the number of items in the <tt>args</tt> list.", 
            "rstrip": "The <tt>line.rstrip()</tt> is unnecessary for correct output.", 
            "options": "The script parses command-line options by treating the arguments as a queue.", 
            "append": "To add an item to the end of a list, we use the <tt>append</tt> method."
        }
    }, 
    "q2": {
        "type": "multiple", 
        "question": "\n<p>Given the following Python script, <tt>env.py</tt>:</p>\n\n<pre>\n#!/usr/bin/env python3\n\nimport os\n\nfor key, value in sorted(os.environ.items()):\n    print('{}={}'.format(key, value))\n</pre>\n\n<p>Which of the following statements are true (select all that apply)?</p>\n", 
        "responses": {
            "evars": "This script prints all environmental variables from the shell.", 
            "nofmt": "Instead of <tt>print('{}={}'.format(key, value))</tt>, we could do <tt>print(key + '=' + value)</tt>.", 
            "dict": "The <tt>os.environ</tt> is a dictionary object.", 
            "svars": "This script prints all the variables inside the script.", 
            "list": "The <tt>os.environ</tt> is a list object.", 
            "oldfmt": "Instead of <tt>print('{}={}'.format(key, value))</tt>, we could do <tt>print('%s=%s' % (key, value))</tt>."
        }
    }
}