Number of features of the model must match the input. Model n_features is 4 and input n_features is 3

For scikit_bring_your_own example, when trying to predict the payload.csv file by running:

`./predict.sh payload.csv text/csv`

There is an error occurring: "Number of features of the model must match the input. Model n_features is 4 and input n_features is 3".

The problem is that payload.csv was not correctly formatted.
**The solution** is to add the header column before the first column.

Here is a zip of the edited CSV file which worked for me:
[payload.csv.zip](https://github.com/awslabs/amazon-sagemaker-examples/files/2917314/payload.csv.zip)