How to receive json POST request using web2py

I'm very new to web2py and I'm trying to use it for testing remote server's application (I send a http POST request using python requests with file to process and expect to get counter POST request with report in json and display it in shell or save to file). I found following code for similar issue for XML data

# Controller code:
def index(): 
    response.headers['content-type'] = 'text/xml'
    xml = request.body.read()  # retrieve the raw POST data
    if len(xml) == 0:
        xml = '<?xml version="1.0" encoding="utf-8" ?><root>no post data</root>'
    return response.render(dict(xml=XML(xml)))

# View code:
{{=xml}}

but I can't make proper changes that will allow to use it for my purpose. So the question is: how to simply receive json data via POST request and save it directly on my computer or to display it somehow using web2py? No buttons, upload fields, data bases needed.. only to get data from incoming request