While forming a request for a Rest Connector, upon tracing the request_PUT page structure shows like this - 

Property A - Value A

Property B - Value B and so on.

But on checking the pyInvokeRESTConnector activity in the tracer, the parameter RequestData, the json format shows incorrect property names like - 

{ "Property A" : "Value A", "Property A" : "Value B", ...... }

This is happening in Pega version 8.3.0