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This is an issue with R language generator.

Description

i have an endpoint for which the return type is a dictionary, say Dictonary(string, Object1)
but when the client is generated using openapi-generator-3.3.4.jar the response is just creating an object of type say Object1 instead of a Dictionary equivalent.

I compared the returnType of endpoint in the generated json using the -DdebugOperations with python against that with R
for Python, it has "returnType" : "dict(str, Object1)
for R, it is "returnType" : "Object1"

so the openapi-generator is not generating the returnType key as an equivalent of dictionary for R langauge.

openapi-generator version

3.3.4

OpenAPI declaration file content or url

R generated structure :
using "java -DdebugOperations -jar openapi-generator-cli-3.3.4.jar generate -l r ......."

       "isRestful" : false,
      "isDeprecated" : false,
      "isCallbackRequest" : false,
      "path" : "/axxx/px/v1/caxxxxxx",
      "operationId" : "get_all_xxxxxx",
      **"returnType" : "Oxxxxxxon",**     //difference in this line with respect to below json
      "httpMethod" : "GET",
      "returnBaseType" : "Oxxxxxon",
      "returnContainer" : "map",
      "summary" : "Get All Oxxxxons",

Python generated structure:
using "java -DdebugOperations -jar openapi-generator-cli-3.3.4.jar generate -l python ......."

      "isRestful" : false,
      "isDeprecated" : false,
      "path" : "/axxx/px/v1/caxxxxxx",
       "operationId" : "get_all_xxxxxx",
      "returnType" : "dict(str, Oxxxxxxon)",    
      "httpMethod" : "GET",
      "returnBaseType" : "Oxxxxxon",
      "returnContainer" : "map",
      "summary" : "Get All Oxxxxons",

From the above the R generation is ignoring the Dictionary and simply returning the bare Object type.
This is causing issue in deserialization in the generated model file.
-->

Command line used for generation

java -DdebugOperations -jar openapi-generator-cli-3.3.4.jar generate -l r

Steps to reproduce

As describe above

Related issues/PRs

NA

@wing328 - looking for your help. Thanks in advance.