code: public ApiResponse<Map<String, String>> getHeadersWithHttpInfo() throws ApiException {
          com.squareup.okhttp.Call call = getHeadersValidateBeforeCall(null);
          Type localVarReturnType = new TypeToken<Map<String, String>>() {
          }.getType();
          return apiClient.execute(call, localVarReturnType);
      }
docs: Debug request headers Echo the request headers for debugging purposes.
  Note that the &#39;Connection&#39; header and any &#39;X-&#39; headers
  are not included
  
  @return ApiResponse&lt;Map&lt;String, String&gt;&gt;
  @throws ApiException
  If fail to call the API, e.g. server error or cannot
  deserialize the response body