csv to nested JSON?
<p>I’m trying to convert a flat structured CSV into a nested JSON structure.  The CSV is generated from SQL which creates multiple rows for each primary id. The CSV is structured as follows:</p>

<pre class="lang-none prettyprint-override"><code>PrimaryId,FirstName,LastName,City,CarName,DogName
100,John,Smith,NewYork,Toyota,Spike
100,John,Smith,NewYork,BMW,Spike
100,John,Smith,NewYork,Toyota,Rusty
100,John,Smith,NewYork,BMW,Rusty
101,Ben,Swan,Sydney,Volkswagen,Buddy
101,Ben,Swan,Sydney,Ford,Buddy
101,Ben,Swan,Sydney,Audi,Buddy
101,Ben,Swan,Sydney,Volkswagen,Max
101,Ben,Swan,Sydney,Ford,Max
101,Ben,Swan,Sydney,Audi,Max
102,Julia,Brown,London,Mini,Lucy
</code></pre>

<p>The desired JSON output is:</p>

<pre><code>{
    "data": [
        {
            "City": "NewYork", 
            "FirstName": "John", 
            "PrimaryId": 100, 
            "LastName": "Smith", 
            "CarName": [
                "Toyota", 
                "BMW"
            ], 
            "DogName": [
                "Spike", 
                "Rusty"
            ]
        }, 
        {
            "City": "Sydney", 
            "FirstName": "Ben", 
            "PrimaryId": 101, 
            "LastName": "Swan", 
            "CarName": [
                "Volkswagen", 
                "Ford", 
                "Audi"
            ], 
            "DogName": [
                "Buddy", 
                "Max"
            ]
        }, 
        {
            "City": "London", 
            "FirstName": "Julia", 
            "PrimaryId": 102, 
            "LastName": "Brown", 
            "CarName": [
                "Mini"
            ], 
            "DogName": [
                "Lucy"
            ]
        }
    ]
}
</code></pre>

<p>Both <a href="https://stackoverflow.com/questions/29631711/python-to-parent-child-json">this post</a> and <a href="https://stackoverflow.com/questions/17043229/create-nested-json-from-csv">this one </a> have helped but I'm yet to create the correct structure.</p>