Question: I have a .csv file that has 25 columns. In this data, column 18 is a People\_ID, and column 19 is a Donation Date. I have pre-sorted the data using Linux so that all People ID's appear together, sorted by donation date in descending order.

Here is where I'm not sure how to proceed. I need to find all lines that have the same People\_ID and Donation Date, sum various values, and then output a single line into the output. So essentially, every line in the file would be either a different customer, or a different donation date by the same customer. Would it be best to use a dictionary using the People\_ID as the key? How would this look syntactically?

I was thinking something like this:

```
with open("file.csv") as csv_file:
for row in csv.reader(csv_file, delimiter=','):
    if row[18] in data_dict:
        # something something

```

Answer: 
As indicated by @user316607, Play should define `application.home` by itself in the [Logger.configure method](https://github.com/playframework/playframework/blob/2.4.x/framework/src/play/src/main/scala/play/api/Logger.scala#L209). If you are seeing the value `application.home_IS_UNDEFINED` instead, and you're using [compile-time dependency injection](https://www.playframework.com/documentation/2.4.x/ScalaCompileTimeDependencyInjection), you'll need to call `Logger.configure` yourself in your `ApplicationLoader` as explained in [this blog post](http://loicdescotte.github.io/posts/play24-compile-time-di/):

```
class MyApplicationLoader extends ApplicationLoader {
  def load(context: Context) = {
    new MyComponents(context).application
  }
}

class MyComponents(context: Context) extends BuiltInComponentsFromContext(context) {
  // You have to call Logger.configure manually or logback won't work
  Logger.configure(context.environment)

  // ... The rest of your app initialization code ...
}

```
I feel stupid. I just realised that it's part of logback and not part of play. You can define your own variables like thus:

```
<property name="USER_HOME" value="/home/sebastien" />

```

Checkout link here for more details:
<http://logback.qos.ch/manual/configuration.html#definingProps>