program on Serverless Data Processing on AWS workshop

Hello, I did the aws workshop on serverless data processing and at the step: https://catalog.us-east-1.prod.workshops.aws/workshops/76d4b4eb-bff7-40c6-a925-7f101ad3bd43/en-US/kinesis/setup/03-cloud9-setup there is a client program which contains the producer and consumer: https://catalog.us-east-1.prod.workshops.aws/workshops/76d4b4eb-bff7-40c6-a925-7f101ad3bd43/en-US/kinesis/setup/03-cloud9-setup. Actually there are two files named producer and consumer and don't have a file extension. I would like to ask in which programming language these files are written and how I can view their contents. Thank you.